Analysis of volatile constituents and chemical relationship of cultivated and wild Angelica dahurica / 南方医科大学学报

OBJECTIVE@#To determine the volatile constituents and their contents in the roots of 5 cultivated Angelica dahurica and one wild A. dahurica and analyze the chemical relationship among the plants of A. dahurica.@*METHODS@#The essential oil was extracted from the roots of 5 cultivated plants of Angelica dahurica and one wild A. dahurica by water steam distillation. Gas chromatography-mass spectrometry (GC-MS) was used to separate and identify all the volatile oil components in the extracts, and their relative contents were calculated with area normalization method. We also conducted clustering analysis and principal component analysis of the volatile oil components.@*RESULTS@#We identified a total of 81 compounds from the roots of the 6 plants of Angelica dahurica, including 27 in Chuanbaizhi (Angelica dahurica cv. 'Hangbaizhi'), 34 in Hangbaizhi (Angelica dahurica cv. 'Hangbaizhi'), 24 in Qibaizhi (Angelica dahurica cv. 'Qibaizhi'), 32 in Yubaizhi (Angelica dahurica cv.'Qibaizhi'), 28 in Bobahizhi (Angelica dahurica cv.'Qibaizhi'), and 34 in Xinganbaizhi (Angelica dahuirca). These compounds included, in the order of their relative contents (from high to low), alkanes, olefins, esters, organic acids and alcohols. Among the common components found in the roots of all the plants of A. dahurica, nonylcyclopropane, cyclododecane and hexadecanoic acid were identified as the volatile oil components that showed the highest relative contents. Clustering analysis of the volatile oil components showed that wild Angelica dahurica (Xing'anbaizhi) and the 5 cultivated Angelica dahurica (Chuanbaizhi, Hangbaizhi, Qibaizhi, Yubaizhi, Bobaizhi) could be divided into two groups, and the cultivated Angelica dahurica could be divided into two subgroups: Chuanbaizhi, Yubaizhi and Hangbahizhi were clustered in one subgroup, and Qibaizhi and Bobaizhi in another. The results of principal component analysis was consistent with those of clustering analysis.@*CONCLUSION@#The main volatile oil components and their contents vary among the 6 plants of A. dahurica. Nonylcyclopropane, cyclododecane and hexadecanoic acid are the most abundant volatile oil components in all the plants of A. dahurica, which can be divided into two clusters.

Palmitic acid suppresses autophagy in neonatal rat cardiomyocytes via the cGAS-STING-IRF3 pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effect of palmitic acid (PA) on autophagy in neonatal rat cardiomyocytes (NRCMs) and explore the underlying mechanism.@*METHODS@#NRCMs were isolated and cultured for 24 h before exposure to 10% BSA and 0.1, 0.3, 0.5, or 0.7 mmol/L PA for 24 h. After the treatments, the expressions of Parkin, PINK1, p62, LC3Ⅱ/ LC3Ⅰ, cGAS, STING and p-IRF3/IRF3 were detected using Western blotting and the cell viability was assessed with CCK8 assay, based on which 0.7 mmol/L was selected as the optimal concentration in subsequent experiments. The effects of cGAS knockdown mediated by cGAS siRNA in the presence of PA on autophagy-related proteins in the NRCMs were determined using Western blotting, and the expressions of P62 and LC3 in the treated cells were examined using immunofluorescence assay.@*RESULTS@#PA at different concentrations significantly lowered the expressions of Parkin, PINK1, LC3 Ⅱ/LC3 Ⅰ and LC3 Ⅱ/LC3 Ⅰ+Ⅱ (P < 0.05), increased the expression of p62 (P < 0.05), and inhibited the viability of NRCMs (P < 0.05). Knockdown of cGAS obviously blocked the autophagy-suppressing effect of PA and improved the viability of NRCMs (P < 0.05).@*CONCLUSION@#PA inhibits autophagy by activating the cGAS-STING-IRF3 pathway to reduce the viability of NRCMs.

Effects of oleic (18: 1n-9) and palmitic (16: 0) fatty acids on the metabolic state of adipocytes / Efectos de los ácidos grasos oleico (18: 1n-9) y palmítico (16: 0) en el estado metabólico del adipocito

Abstract Background: Elevated serum-free fatty acid (FFA) levels induce insulin resistance (IR) or a protective mechanism to IR development in humans; it depends on FFA type. Objetive: This study explores the effects of oleic (OLA - unsatured) and palmitic (PAM - saturated) fatty acids on insulin action in mature adipocytes effect. Methods: Cells were incubated 18 h with or without OLA and PAM at 250 μM, and 500 μM. After the culture period, were measured: adipocyte viability, size, fatty acids mobilisation, insulin signalling proteins, and glucose uptake. Results: Adipocytes exhibited optimal viability tolerances regardless of the kinds of fatty acids used for treatment. However, adipocytes were hypertrophic after OLA and PAM stimuli. Additionally, lipogenesis (lipid synthesis), and lipolysis (lipid breakdown) were significantly increased by treatment with OLA, or PAM (500 μM) compared to control. Moreover, OLA results showed that there was no significant reduction in signalling cascades, except for a downstream proinflammatory response. Instead, PAM hypertrophic adipocytes were insulin resistant with alteration of proinflammatory and stress markers. Conclusions: Current findings suggest that PAM induces insulin resistance, mitochondrial and reticulum stress on fat cells compared to those treated with OLA that, protects adipocytes to all those alterations.

Resumen Introducción: Los niveles elevados de ácidos grasos libres (AGL) en suero inducen resistencia a insulina (RI) o un mecanismo de protección del desarrollo de RI en humanos, esto depende del tipo de AGL. Objetivo: Este estudio explora los efectos de los ácidos grasos oleico (insaturados - OLA) y palmítico (saturados - PAM) sobre la insulina en adipocitos maduros. Métodos: Las células se incubaron 18 h con o sin OLA y PAM a 250 μM y 500 μM. Después del período de cultivo, se evaluó en adipocitos: viabilidad, tamaño, movilización de ácidos grasos, proteínas de señalización de insulina y absorción de glucosa. Resultados: Los adipocitos mostraron viabilidad óptima independientemente de los tipos de ácidos grasos utilizados en el tratamiento. Los adipocitos eran hipertróficos tras estimulo con OLA y PAM. La lipogénesis (síntesis de lípidos) y la lipólisis (degradación de lípidos) aumentaron significativamente con el tratamiento con OLA o PAM (500 μM) en comparación con el control. En los resultados de OLA no se evidenció una reducción significativa en las cascadas de señalización de insulina, a excepción de una respuesta proinflamatoria posterior. En cambio, los adipocitos hipertróficos tratados con PAM presentaron resistencia a la insulina y alteración de los marcadores proinflamatorios y de estrés. Conclusiones: Nuestros hallazgos sugieren que PAM induce resistencia a la insulina, estrés mitocondrial y del retículo en las células grasas en comparación con aquellos tratados con OLA, AGL que, en cambio, protegen a los adipocitos de todas esas alteraciones.

Efeito da adição do ácido palmítico e da vitamina E ao diluidor Tris-gema na criopreservação de sêmen canino / Effect of addition of palmitic acid and Vitamin E to the Tris-egg yolk diluter in canine semen cryopreservation

Canine sperm is a very delicate cell that is quite susceptible to oxidative stress since the cytoplasm is restricted and features little antioxidant reserves. Furthermore, the sperm membrane has some polyunsaturated fatty acids sensitive to lipid peroxidation, which makes it important to addition antioxidant substances to the diluter aiming at decreasing such stress to the sperm cell, particularly during seminal cryopreservation. Several antioxidants have been used in this process in some domestic animal's species, however, the use of palmitic acid has been little reported in works on cryopreservation of semen of the canine species. Hence, this study aimed to assess the effect of addition antioxidants palmitic acid and vitamin E to the Tris-egg yolk diluter on the semen quality of dogs after thawing. Samples were collected from the ejaculates of 4 adult dogs, apparently healthy, of the American Pit Bull Terrier breed of kennels in the city of Teresina, PI, places where the pre-freezing procedures of the dog's semen were performed. The samples were diluted in Tris citric acid fructose (3.28 g Tris-hydroxymethyl-aminomethane, 1.78 g citric acid monohydrate and 1.25 g D-fructose), dissolved in 100 mL distilled water, and added 20% egg yolk and 6% glycerol, at the concentration of 100x106 sptz/mL. The semen samples were divided into 3 mL aliquots to form 3 experimental groups: G1 - Only Tris-egg yolk (Control group); G2 - Tris-egg yolk + 100 µM palmitic acid; and G3 - Tris-egg yolk + 116 µM vitamin E. Semen was collected weekly over a period of little over 2 months. After thawing, thermorresistance test (TTR) was carried out at 0, 30, 60, and 90 min to assess spermatics motility and vigor, in addition to analysis of integrity of plasma membrane, acrosomal membrane and mitochondrial activity of the sperm, using fluorescent probes. These assessments were performed out at the Animal Reproduction Biotechnology Laboratory (LBRA/UFPI). In the TTR, G2 and G3 didn't exhibit significant results for spermatics motility or vigor when compared with the control group. The palmitic acid and vitamin E also had no significant effects on the parameters of acrosomal membrane integrity or mitochondrial activity. However, sperm cryopreserved with the addition of palmitic acid exhibited significant differences for plasma membrane integrity, providing greater protection to the sperm cells in G2. The palmitic acid is one of the most saturated fatty acids in human semen, with reports of great proportions also in the seminal plasma of dogs. Its main role is to protect the plasma membrane from external damage, improving viability and fertility of the sperm after cryopreservation. Data is scarce in the literature on the composition of fatty acids in canine semen and regarding the use of palmitic acid as a seminal antioxidant in that species, which grants further studies aiming to investigate such valuable information for canine reproduction. It is concluded that addition palmitic acid at 100µM concentration to the Tris-egg yolk diluter was able to preserve the integrity of the plasma membrane during the process of cryopreservation of canine semen.(AU)

Guanxin Zhitong Capsules attenuate human endothelial cell damage induced by palmitic acid via MAPK signaling pathway / 中国中药杂志

The present study observed the effect of Guanxin Zhitong Capsules(GXZT) on the lipotoxicity of vascular endothelial cells and investigated the mechanism of GXZT in atherosclerosis treatment. The lipotoxicity model in human umbilical vein endothelial cells(HUVECs) was induced by palmitic acid(PA) stimulation. These cells were divided into a normal control group(NC, 15% normal serum), a model group(PA, 0.6 mmol·L~(-1) PA+15% normal serum), a high-dose GXZT group(GXZT-H, 0.6 mmol·L~(-1) PA+15% GXZT-medicated serum), a medium-dose GXZT group(GXZT-M, 0.6 mmol·L~(-1) PA+10% GXZT-medicated serum+5% normal serum) and a low-dose GXZT group(GXZT-L, 0.6 mmol·L~(-1) PA+5% GXZT-medicated serum+10% normal serum). HUVECs were detected for cell viability by cell counting kit-8(CCK-8) assay, apoptosis by flow cytometry, mitochondrial membrane potential(MMP) by JC-1 labeled laser scanning confocal microscopy, and total and phosphorylated proteins of p38, ERK1/2, and JNK1/2 in the mitogen-activated protein kinases(MAPK) signaling pathway by Western blot. The phosphorylated level was calcula-ted. Compared with the NC group, the PA group showed decreased cell viability and MMP(P<0.01, P<0.01), elevated apoptosis(P<0.01), and up-regulated phosphorylated levels of p38, ERK1/2, and JNK1/2(P<0.01, P<0.01, P<0.01). Compared with the PA group, the GXZT-H, GXZT-M, and GXZT-L groups showed increased cell viability and MMP(P<0.01, P<0.01, P<0.01), reduced apoptosis(P<0.01), and down-regulated protein expression and phosphorylated levels of p38, ERK1/2 and JNK1/2 in the MAPK signaling pathway(P<0.01, P<0.01, P<0.01). In conclusion, the results suggest that GXZT functions via blocking MAPK signaling pathway to relieve the damage of HUVECs induced by PA.

Lipopolysaccharide inhibits lipophagy in HepG2 cells via activating mTOR pathway / 生理学报

This study aimed to investigate the effect of lipopolysaccharide (LPS) on lipophagy in hepatocytes and the underlying mechanism. Human hepatoma cell line HepG2 was cultured in vitro, treated with 0.1 mmol/L palmitic acid (PA), and then divided into control group (0 μg/mL LPS), LPS group (10 μg/mL LPS), LPS+DMSO group and LPS+RAPA (rapamycin, 10 μmol/L) group. Lipid accumulation in hepatocytes was observed by oil red O staining. The autophagic flux of the cells was assessed using confocal laser scanning microscope after being transfected with autophagy double-labeled adenovirus (mRFP-GFP-LC3). The level of intracellular lipophagy was visualized by the colocalization of lipid droplets (BODIPY 493/503 staining) and lysosomes (lysosome marker, lysosomal associated membrane protein 1, LAMP1). The expression levels of mammalian target of rapamycin (mTOR), phosphorylated mTOR (p-mTOR), ribosome protein subunit 6 kinase 1 (S6K1), p-S6K1, LC3II/I and P62 protein were examined by Western blot. The results showed that the number of red lipid droplets stained with oil red O was significantly increased in LPS group compared with that in control group (P < 0.001). Moreover, in LPS group, the number of autophagosomes was increased, while the number of autophagolysosomes and the colocalization rate of LAMP1 and BODIPY were significantly decreased (P < 0.05). Meanwhile, the ratios of p-mTOR/mTOR and p-S6K1/S6K1, the ratio of LC3II/LC3I and the protein expression of P62 were significantly increased (P < 0.05) in LPS group. Furthermore, compared with LPS+DMSO group, RAPA treatment obviously reduced the number of lipid droplets and autophagosomes, and raised the number of autophagolysosomes and the colocalization rate of LAMP1 and BODIPY (P < 0.05). In conclusion, the results demonstrate that LPS inhibits lipophagy in HepG2 cells via activating mTOR signaling pathway, thereby aggravating intracellular lipid accumulation.

Period circadian clock 3 inhibits palmitic acid-induced oxidative stress and inflammatory factor secretion in podocytes / 中南大学学报(医学版)

OBJECTIVES@#High fat-induced podocyte injury is one of the important factors leading to obesity related nephropathy (ORG), but the mechanism is not clear. This study aims to explore the mechanism of period circadian clock 3 (PER3) in the oxidative stress and inflammation induced by palmitic acid (PA) in podocytes.@*METHODS@#The C57BL/6J mice were fed with chow and high-fat diet for 16 weeks. The PER3 expression in kidney tissues were detected in the normal body weight group and the obesity group. The PER3 mRNA and protein expression were detected after the podocytes were induced with different concentrations (0, 50, 150 and 300 μmol/L) of PA for 48 h. The PER3 mRNA and protein expression were detected after the podocytes were induced with 150 μmol/L PA for 0, 24, 36, and 48 h. Triglyceride (TG) levels were examined in the PA group, the adenovirus (ad)-PER3+PA group, and the siRNA-PER+PA group after the podocytes were transfected by Ad-PER3 or small interfering RNA (siRNA)-PER3 for 48 h and subsequently were induced with 150 μmol/L PA for 48 h. The differential gene expression was detected using RNA sequencing (RNA-seq) after podocytes were transfected by siRNA-PER3 (siRNA-PER3 group) and siRNA-control (siRNA-control group), respectively. The mRNA levels of nephrin, podocin, podocalyxin, podoplanin, superoxide dismutase 1 (SOD1), glutathione peroxidase 1 (GPX1), catalase (CAT), and the levels of malondialdehyde (MDA), glutathione (GSH), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β) and interleukin-2 (IL-2) were detected after podocytes were transfected with Ad-PER3 or Ad-control for 48 h and then they were induced by 150 μmol/L PA for 48 h.@*RESULTS@#The PER3 was down-regulated in the obesity group compared with the normal body weight group (@*CONCLUSIONS@#PER3 can decrease the PA-induced oxidative stress and inflammatory factor secretion via inhibiting the lipogenesis in podocytes.

Associação entre Staphylococcus epidermidis e o nível de ácido palmítico em pacientes com acne vulgar / The association between Staphylococcus epidermidis and palmitic acid level in patients with acne vulgaris

INTRODUÇÃO: A acne vulgar é um distúrbio inflamatório da glândula pilossebácea. O ácido palmítico é um dos principais tipos de ácidos graxos livres e pode desempenhar um papel na patogênese da acne. Além disso, estudos recentes sugeriram que o Staphylococcus epidermidis pode estar envolvido na acne. OBJETIVO: Explorar a associação entre a Staphylococcus epidermidis e o ácido palmítico na acne vulgar. MÉTODOS: 43 estudantes do ensino médio de uma área urbana do sul de Sulawesi, na Indonésia, foram incluídos. O nível de ácido palmítico foi medido utilizando cromatografia gasosa e os comedões foram cultivados para detectar o perfil do microbioma. O teste de Mann-Whitney foi utilizado para analisar a diferença do nível palmítico médio entre os grupos com diferentes graus de gravidade da acne vulgar. RESULTADOS: 14 pacientes (32,6%) apresentavam acne vulgar leve, enquanto 14 e 15 pacientes apresentavam acne vulgar moderada e grave, respectivamente. O grupo grave e moderado apresentou nível de ácido palmítico significativamente maior em comparação ao grupo leve. A análise de subgrupo de pacientes com acne vulgar moderada e grave, positiva para S. epidermidis, mostrou um nível significativamente maior de ácido palmítico comparado ao grupo leve. CONCLUSÕES: Esses resultados sugerem que S. epidermidis pode estar associado ao nível de ácido palmítico e pode contribuir na patogênese da acne.

INTRODUCTION: Acne vulgaris is an inflammatory disorder of the pilosebaceous gland. Palmitic acid is one of the major types of free fatty acid and may play a role in acne pathogenesis. In addition, recent studies suggested that Staphylococcus epidermidis might be involved in acne. OBJECTIVE: To explore the association between Staphylococcus epidermidis and palmitic acid in acne vulgaris. METHODS: Forty-three high school students at an urban area in South Sulawesi, Indonesia, were included. The palmitic acid level was measured using gas chromatography and comedone was cultured to detect the microbiota profile. Mann-Whitney test was used to analyze the median palmitic level diference between groups with different acne vulgaris severity. RESULTS: Fourteen patients (32.6%) had mild acne vulgaris, while 14 and 15 patients had moderate and severe acne vulgaris, respectively The severe and moderate group showed significantly higher palmitic acid level compared with the mild group. Subgroup analysis of patients with moderate and severe acne vulgaris positive for S. epidermidis showed a significantly higher palmitic acid level compared with the mild group. CONCLUSIONS: This result suggests that S. epidermidis may be associated with the palmitic acid level and may contribute to acne pathogenesis.

Dietary effect of Lactobacillus plantarum CJLP55 isolated from kimchi on skin pH and its related biomarker levels in adult subjects / 한국영양학회지

PURPOSE: The skin pH is maintained by epidermal lactate, free fatty acids (FFAs), and free amino acids (FAAs). As a significant determinant of skin health, the skin pH is increased (less acidic) under abnormal and aged skin conditions. In a search for dietary alternatives that would promote an acidic skin pH, this study investigated the dietary effects of Lactobacillus plantarum CJLP55 isolated from Korean kimchi on the skin pH, and epidermal levels of lactate, FFAs, and FAAs in adult subjects. METHODS: Seventy eight subjects (mean age 24.9 ± 0.5 years, range 19 ~ 37 years) were assigned randomly to ingest CJLP55, Lactobacillus strain from kimchi, (n = 39, CJLP group) or placebo supplements (n = 39, placebo group) for 12 weeks in a double-blind, placebo-controlled trial. Skin pH and epidermal levels of lactate, FFAs and FFAs were assessed at 0, 6 and 12 weeks. RESULTS: Although significant decreases in skin pH were observed in both the CJLP and placebo groups at 6 weeks, the skin pH was decreased significantly only in the CJLP group at 12 weeks. In parallel, the epidermal level of lactate in the CJLP group was also increased by 25.6% at 12 weeks. On the other hand, the epidermal level of FAAs were not altered in the CJLP and placebo groups, but the epidermal level of total FFAs, including palmitic acid and stearic acid, was lower in the CJLP group than in the placebo group over 12 weeks. The changes in the other FFAs, such as palmitoleic acid and oleic acid, were similar in the CJLP and placebo groups over 12 weeks. CONCLUSION: Overall, a dietary supplement of CJLP55 promotes acidic skin pH with a selective increase in epidermal lactate in adult subjects.

Emodin exerts protective effect against palmitic acid-induced endoplasmic reticulum stress in HepG2 cells / 한국영양학회지

PURPOSE: Protein overloading in the endoplasmic reticulum (ER) leads to endoplasmic reticulum stress, which exacerbates various disease conditions. Emodin, an anthraquinone compound, is known to have several health benefits. The effect of emodin against palmitic acid (PA) - induced ER stress in HepG2 cells was investigated. METHODS: HepG2 cells were treated with varying concentrations of palmitic acid to determine the working concentration that induced ER stress. ER stress associated genes such as ATF4, XBP1s, CHOP and GRP78 were checked using RT- PCR. In addition, the expression levels of unfolded protein response (UPR) associated proteins such as IRE1α, eIF2α and CHOP were checked using immunoblotting to confirm the induction of ER stress. The effect of emodin on ER stress was analyzed by treating HepG2 cells with 750 µM palmitic acid and varying concentrations of emodin, then analyzing the expression of UPR associated genes. RESULTS: It was evident from the mRNA and protein expression results that palmitic acid significantly increased the expression of UPR associated genes and thereby induced ER stress. Subsequent treatment with emodin reduced the mRNA expression of ATF4, GRP78, and XBP1s. Furthermore, the protein levels of p-IRE1α, p-elF2α and CHOP were also reduced by the treatment of emodin. Analysis of sirtuin mRNA expression showed that emodin increased the levels of SIRT4 and SIRT7, indicating a possible role in decreasing the expression of UPR-related genes. CONCLUSION: Altogether, the results suggest that emodin could exert a protective effect against fatty acid-induced ER stress and could be an agent for the management of various ER stress related diseases.

Metabolic Profiling of Plasma from Pancreatic Cancer Patients in Korea / 대한췌담도학회지

BACKGROUND/AIMS: Pancreatic cancer (PC) patients have poor prognoses because this cancer is typically diagnosed at an advanced stage and the therapeutic options are limited. We examined the potential of metabolic profiling for early diagnosis and identification of potential therapeutic targets. METHODS: Ten patients and 10 healthy volunteer controls older than 20 years of age were enrolled between May and December 2015. The patients were confirmed to have pancreatic ductal adenocarcinoma cytologically or histologically. Blood plasma samples were derivatized and analyzed by gas chromatography mass spectrometry (GC-MS). Untargeted GC-MS data were analyzed using statistical methods, including Wilcoxon rank-sum test and principal component analyses. RESULTS: L-lysine was 1.36-fold higher in patients than in healthy controls (p<0.05). L-leucine was 0.63-fold lower (p<0.01) and palmitic acid was 0.93-fold lower (p<0.5) in patients than in controls. Orthogonal partial least squared-discriminant analysis revealed significant differences between the patients and controls. CONCLUSIONS: This study suggests that the metabolic profiles of patients with PC are distinct from those of the healthy population. Further studies are required to develop methods for early diagnosis and identify therapeutic targets.

Differential effects of saturated and unsaturated fatty acids on vascular reactivity in isolated mesenteric and femoral arteries of rats

Free fatty acid (FFA) intake regulates blood pressure and vascular reactivity but its direct effect on contractility of systemic arteries is not well understood. We investigated the effects of saturated fatty acid (SFA, palmitic acid), polyunsaturated fatty acid (PUFA, linoleic acid), and monounsaturated fatty acid (MUFA, oleic acid) on the contractility of isolated mesenteric (MA) and deep femoral arteries (DFA) of Sprague–Dawley rats. Isolated MA and DFA were mounted on a dual wire myograph and phenylephrine (PhE, 1–10 µM) concentration-dependent contraction was obtained with or without FFAs. Incubation with 100 µM of palmitic acid significantly increased PhE-induced contraction in both arteries. In MA, treatment with 100 µM of linoleic acid decreased 1 µM PhE-induced contraction while increasing the response to higher PhE concentrations. In DFA, linoleic acid slightly decreased PhE-induced contraction while 200 µM oleic acid significantly decreased it. In MA, oleic acid reduced contraction at low PhE concentration (1 and 2 µM) while increasing it at 10 µM PhE. Perplexingly, depolarization by 40 mM KCl-induced contraction of MA was commonly enhanced by the three fatty acids. The 40 mM KCl-contraction of DFA was also augmented by linoleic and oleic acids while not affected by palmitic acid. SFA persistently increased alpha-adrenergic contraction of systemic arteries whereas PUFA and MUFA attenuated PhE-induced contraction of skeletal arteries. PUFA and MUFA concentration-dependent dual effects on MA suggest differential mechanisms depending on the types of arteries. Further studies are needed to elucidate underlying mechanisms of the various effects of FFA on systemic arteries.

Nicotinamide riboside regulates inflammation and mitochondrial markers in AML12 hepatocytes

BACKGROUND/OBJECTIVES: The NAD+ precursor nicotinamide riboside (NR) is a type of vitamin B3 found in cow's milk and yeast-containing food products such as beer. Recent studies suggested that NR prevents hearing loss, high-fat diet-induced obesity, Alzheimer's disease, and mitochondrial myopathy. The objective of this study was to investigate the effects of NR on inflammation and mitochondrial biogenesis in AML12 mouse hepatocytes. MATERIALS/METHODS: A subset of hepatocytes was treated with palmitic acid (PA; 250 µM) for 48 h to induce hepatocyte steatosis. The hepatocytes were treated with NR (10 µM and 10 mM) for 24 h with and without PA. The cell viability and the levels of sirtuins, inflammatory markers, and mitochondrial markers were analyzed. RESULTS: Cytotoxicity of NR was examined by PrestoBlue assay. Exposure to NR had no effect on cell viability or morphology. Gene expression of sirtuin 1 (Sirt1) and Sirt3 was significantly upregulated by NR in PA-treated hepatocytes. However, Sirt1 activities were increased in hepatocytes treated with low-dose NR. Hepatic pro-inflammatory markers including tumor necrosis factor-alpha and interleukin-6 were decreased in NR-treated cells. NR upregulated anti-inflammatory molecule adiponectin, and, tended to down-regulate hepatokine fetuin-A in PA-treated hepatocytes, suggesting its inverse regulation on these cytokines. NR increased levels of mitochondrial markers including peroxisome proliferator-activated receptor γ coactivator-1α, carnitine palmitoyltransferase 1, uncoupling protein 2, transcription factor A, mitochondrial and mitochondrial DNA in PA-treated hepatocytes. CONCLUSIONS: These data demonstrated that NR attenuated hepatic inflammation and increased levels of mitochondrial markers in hepatocytes.

Palmitic acid-induced lipotoxicity promotes a novel interplay between Akt-mTOR, IRS-1, and FFAR1 signaling in pancreatic ß-cells

BACKGROUND: Free fatty acid receptor 1 (FFAR1) is G-protein coupled receptor predominantly expressed in pancreatic ß-cells that is activated by a variety of free fatty acids (FFAs). Once activated, it promotes glucose-stimulated insulin secretion (GSIS). However, increased levels of FFAs lead to lipotoxicity, inducing loss of ß-cell function. FFAR1 plays a key role in the development of type 2 diabetes (T2D), and previous studies have indicated the importance of developing anti-diabetic therapies against FFAR1, although its role in the regulation of ß-cell function remains unclear. The present study investigated the role of FFAR1 under lipotoxic conditions using palmitic acid (PA). The rat insulinoma 1 clone 832/13 (INS-1 832/13) cell line was used as a model as it physiologically resembles native pancreatic ß-cells. Key players of the insulin signaling pathway, such as mTOR, Akt, IRS-1, and the insulin receptor (INSR1ß), were selected as candidates to be analyzed under lipotoxic conditions. RESULTS: We revealed that PA-induced lipotoxicity affected GSIS in INS-1 cells and negatively modulated the activity of both IRS-1 and Akt. Reduced phosphorylation of both IRS-1 S636/639 and Akt S473 was observed, in addition to decreased expression of both INSR1ß and FFAR1. Moreover, transient knockdown of FFAR1 led to a reduction in IRS-1 mRNA expression and an increase in INSR1ß; mRNA. Finally, PA affected localization of FFAR1 from the cytoplasm to the perinucleus. CONCLUSIONS: In conclusion, our study suggests a novel regulatory involvement of FFAR1 in crosstalk with mTOR-Akt and IRS-1 signaling in ß-cells under lipotoxic conditions.

Palmitoylation of heat shock protein 90 in mouse sperm / 生理学报

Protein palmitoylation, one of post-translation modifications, refers to the addition of saturated 16-carbon palmitic acid to cysteine residues via the thioester bond. It plays key roles in various functional activities, such as the interaction, stability and location of proteins. Heat shock protein 90 (Hsp90), an important molecular chaperone, has been reported to be involved in sperm capacitation. However, it remains unclear whether protein palmitoylation exists in sperm and whether Hsp90 in sperm is palmitoylated under different physiological conditions. In this study, we examined whether the protein palmitoylation is present in mouse cauda epididymis sperm using acyl-biotin exchange method, predicted the potential palmitoylated sites of Hsp90 by the software CSS-Palm 4.0 and detected the palmitoylated Hsp90 in the mouse sperm from caput epididymis and cauda epididymis by immunoprecipitation. We found that some proteins, approximately 50, 65, 72, 85 and 130 kDa, were palmitoylated in mouse cauda epididymis sperm. Five sites in two Hsp90 isoforms were predicted to be palmitoylated. The results also showed that Hsp90 in mouse sperm was palmitoylated and its palmitoylation level was involved in different physiological conditions: the palmitoylation level of cauda epididymis sperm was higher than that of caput epididymis sperm; and the palmitoylation level after capacitation was much higher than that before capacitation. In conclusion, this study reveals that protein palmitoylation is present in mouse sperm and the palmitoylated Hsp90 is associated with different physiological conditions in sperm.

A Combination of Short and Simple Surfactant Protein B and C Analogues as a New Synthetic Surfactant: In Vitro and Animal Experiments

PURPOSE: Pulmonary surfactants for preterm infants contain mostly animal-derived surfactant proteins (SPs), which are essential for lowering surface tension. We prepared artificial pulmonary surfactants using synthetic human SP analogs and performed in vitro and in vivo experiments. MATERIALS AND METHODS: We synthesized peptide analogues that resemble human SP-B (RMLPQLVCRLVLRCSMD) and SP-C (CPVHLKRLLLLLLLLLLLLLLLL). Dipalmitoylphosphatidylcholine (DPPC), phosphatidylglycerol (PG), and palmitic acid (PA) were added and mixed in lyophilized to render powdered surfactant. Synsurf-1 was composed of DPPC:PG:PA:SP-B (75:25:10:3, w/w); Synsurf-2 was composed of DPPC:PG:PA:SP-C (75:25:10:3, w/w); and Synsurf-3 was composed of DPPC:PG:PA:SP-B:SP-C (75:25:10:3:3, w/w). We performed in vitro study to compare the physical characteristics using pulsating bubble surfactometer and modified Wilhelmy balance test. Surface spreading and adsorption test of the surfactant preparations were measured. In vivo test was performed using term and preterm rabbit pups. Pressure-volume curves were generated during the deflation phase. Histologic findings were examined. RESULTS: Pulsating bubble surfactometer readings revealed following minimum and maximum surface tension (mN/m) at 5 minutes: Surfacten® (5.5±0.4, 32.8±1.6), Synsurf-1 (16.7±0.6, 28.7±1.5), Synsurf-2 (7.9±1.0, 33.1±1.6), and Synsurf-3 (7.1±0.8, 34.5±1.0). Surface spreading rates were as follows: Surfacten® (27 mN/m), Synsurf-1 (43 mN/m), Synsurf-2 (27 mN/m), and Synsurf-3 (27 mN/m). Surface adsorption rate results were as follows: Surfacten® (28 mN/m), Synsurf-1 (35 mN/m), Synsurf-2 (29 mN/m), and Synsurf-3 (27 mN/m). The deflation curves were best for Synsurf-3; those for Synsurf-2 were better than those for Surfacten®. Synsurf-1 was the worst surfactant preparation. Microscopic examination showed the largest aerated area of the alveoli in the Synsurf-3 group, followed by Synsurf-1 and Surfacten®; Synsurf-2 was the smallest. CONCLUSION: Synsurf-3 containing both SP-B and SP-C synthetic analogs showed comparable and better efficacy than commercially used Surfacten® in lowering surface tension, pressure-volume curves, and tissue aerated area of the alveoli.

Effects of high glucose with or without other metabolic substrates on alpha-adrenergic contractions in rat mesenteric and femoral arteries

Hyperglycemia is associated with an increased risk of cardiovascular diseases. It has been demonstrated that chronic exposure to high glucose impaired endothelial functions. However, specific effects of short-term exposure to high glucose on vascular reactivity are controversial. Moreover, the combined effects of other metabolic substrates such as free fatty acids (FFA) on vascular reactivity remain poorly understood. Here we investigate the effects of short-term exposure to high glucose with or without other metabolic substrates including FFAs termed “nutrition full” (NF) solution, on mesenteric (MA) and deep femoral arteries (DFA) of rats. Arterial ring segments were mounted in a double-wire myograph. Contraction in response to phenylephrine (PhE) was determined in control (5 mM) and high glucose (23 mM, HG) environments over a 30 min period. In both arteries, PhE-inducedvasocontraction was enhanced by pre-incubation of HG solution. A combined incubation with HG and palmitic acid (100 µM) induced similar sensitization of PhE-contractions in both arteries. In contrast, high K⁺-induced contractions were not affected by HG. Interestingly, pre-incubation with NF solution decreased PhE-induced contraction in MA but increased the contraction in DFA. In NF solution, the HG-induced facilitation of PhE-contraction was not observed in MA. Furthermore, the PhE-induced contraction of DFA was attenuated by HG in NF solution. Our results demonstrate that the sensitization of PhE-induced arterial contraction by HG is differentially affected by other metabolic substrates. The conversation of skeletal arterial contractility by HG in NF solution requires careful interpretation of the previous in vitro studies where only glucose is included in physiological salt solutions. Further studies are required to elucidate the mechanism underlying the inconsistent effect of NF solution on MA and DFA.

Effects of berberine and cinnamic acid on palmitic acid-induced intracellular triglyceride accumulation in NIT-1 pancreatic β cells / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the effects of berberine (BBR) and cinnamic acid (CA), the main active components in Jiaotai Pill (, JTP), on palmitic acid (PA)-induced intracellular triglyceride (TG) accumulation in NIT-1 pancreatic β cells.</p><p><b>METHODS</b>Cells were incubated in culture medium containing PA (0.25 mmol/L) for 24 h. Then treatments with BBR (10 μmol/L), CA (100 μmol/L) and the combination of BBR and CA (BBR+CA) were performed respectively. Intracellular lipid accumulation was assessed by Oil Red O staining and TG content was measured by colorimetric assay. The expression of adenosine monophosphate-activated protein kinase (AMPK) protein and its downstream lipogenic and fatty acid oxidation genes, including fatty acid synthase (FAS), acetyl-coA carboxylase (ACC), phosphorylation acetyl-coA carboxylase (pACC), carnitine acyl transferase 1 (CPT-1) and sterol regulating element binding protein 1c (SREBP-1c) were determined by Western blot or real time polymerase chain reaction.</p><p><b>RESULTS</b>PA induced an obvious lipid accumulation and a significant increase in intracellular TG content in NIT-1 cells. PA also induced a remarkable decrease in AMPK protein expression and its downstream targets such as pACC and CPT-1. Meanwhile, AMPK downstream lipogenic genes including SREBP-1c mRNA, FAS and ACC protein expressions were increased. Treatments with BBR and BBR+CA, superior to CA, significantly reversed the above genes changes in NIT-1 pancreatic β cells. However, the synergistic effect of BBR and CA on intracellular TG content was not observed in the present study.</p><p><b>CONCLUSION</b>It can be concluded that in vitro, BBR and BBR+CA could inhibit PA-induced lipid accumulation by decreasing lipogenesis and increasing lipid oxidation in NIT-1 pancreatic β cells.</p>

Palmitic acid induces hepatocellular oxidative stress and activation of inflammasomes / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the effect of palmitic acid (PA) on oxidative stress and activation of inflammasomes in hepatocytes.</p><p><b>METHODS</b>To test the dose-dependent effect of PA on normal murine hepatocytes AML12, the cells were treated with 0, 0.15, 0.25 and 0.4 mmol/L of palmitic acid (PA). The cells were also divided into blank control group, 0.25 mmol/L PA group and 0.25 mmol/L PA+N-acetylcysteine (NAC) group to examine the effect of reactive oxygen species (ROS) on the activation of inflammasomes. After 24 h of treatment, lipid accumulation, total ROS, mitochondrial ROS, expression and localization of NOX4, and expressions of inflammasomes and IL-1β were detected in the hepatocytes.</p><p><b>RESULTS</b>Compared with the control cells, PA treatment of the cells significantly increased cytoplasmic lipid accumulation, concentrations of total ROS (12 463.09±2.72 vs 6691.23±2.45, P=0.00) and mitochondrial ROS (64.98±0.94 vs 45.04±0.92, P=0.00), and the expressions of NOX4, NLRP3, ASC, caspase-1, and IL-1β (1603.52±1.32 vs 2629.33±2.57, P=0.00). The mitochondria and NOX4 were found to be co-localized in the cytoplasm. NAC obviously reduced cellular ROS level stimulated by PA (7782.15±2.87 vs 5445.6±1.17, P=0.00) and suppressed the expressions of NLRP3, ASC and caspase-1.</p><p><b>CONCLUSION</b>PA treatment can stimulate lipid accumulation in hepatocytes and induce oxidative stress through NOX4 and mitochondria pathway to activate inflammasomes and stimulate the secretion of IL-1β.</p>

Dietary effect of green tea extract on epidermal levels of skin pH related factors, lactate dehydrogenase protein expression and activity in UV-irradiated hairless mice / 한국영양학회지

PURPOSE: Skin pH, an indicator of skin health, is maintained by various organic factors, which include lactate, free amino acid (FAA), and free fatty acid (FFA). As skin ages or with illness, skin pH becomes less acidic, and functional food has been developed to maintain the acidic pH of skin. In this study, we determined the dietary effect of green tea extract (GTE) on skin pH of photo-aged mice, as measured by epidermal levels of lactate, FAA, and FFA. The protein expression and activity of lactate dehydrogenase (LDH), an enzyme of pyruvate reduction for lactate generation, was further determined. METHODS: Albino hairless mice were fed a control diet (group UV+) or a diet with 1% GTE (group GTE) in parallel with UV irradiation for 10 weeks. A normal control group was fed a control diet without UV irradiation for 10 weeks (group UV-). RESULTS: Skin pH was higher (less acidic) in group UV+ than in group UV-. In parallel, epidermal levels of lactate and FFA, as well as of LDH protein expression and activity, were reduced in group UV+. Dietary supplementation of GTE (group GTE) reduced skin pH to similar to the level of group UV-, and inversely increased epidermal levels of lactate, LDH protein expression and activity, but not of FFA. Although epidermal levels of FAA were similar in groups UV- and UV+, it was increased in group GTE to a level higher than in group UV-. In further analysis of major FFA, epidermal levels of palmitic acid [16:0], oleic acid [18:1(n-9)], and linoleic acid [18:2(n-6), but not of stearic acid [18:0] in group GTE were similar to or lower than those in group UV+. CONCLUSION: Dietary GTE normalized skin pH with increased levels of lactate and FAA, as well as with increased protein expression and activity of LDH in the epidermis of UVB irradiated hairless mice.