Impact of Lactobacillus acidophilus and Its Combination with Isoflavone Products on Calcium Status, Calcium Transporters, and Bone Metabolism Biomarkers in a Post-Menopausal Osteoporotic Rat Model.

Osteoporosis in menopausal women requires alternatives to current medications, considering their adverse effects. In this context, probiotics and isoflavone products are promising dietary interventions. The objective of our study was to examine the impacts of Lactobacillus acidophilus and its combination with daidzein and tempeh on calcium status, calcium transporters, and bone metabolism biomarkers in a post-menopausal osteoporotic rat model. A total of 48 female Wistar rats were exposed to a two-stage experiment involving calcium deficit induction and subsequent dietary interventions across six groups. Calcium levels, the gene expression of TRPV5 and TRPV6 calcium transporters, bone histopathology, serum bone metabolism markers, and blood biochemistry were evaluated. The results revealed that, while decreasing serum calcium levels, the groups that received the probiotic L. acidophilus and isoflavone combination exhibited increased bone metabolism biomarkers and decreased calcium transporter expressions, akin to the effects of bisphosphonate. Additionally, significant improvements in bone histopathology were observed in these groups. However, the group receiving probiotic L. acidophilus alone did not exhibit significant changes in bone resorption biomarkers, calcium transporter expression, or various blood parameters. Meanwhile, the combination of probiotic L. acidophilus with tempeh positively influenced hematological parameters and reduced cholesterol and triglyceride levels, but it led to elevated blood glucose levels. Correlation analyses highlighted associations between serum calcium levels, calcium transporter expression, and bone metabolism biomarkers. In conclusion, our findings suggest that the daily consumption of probiotic L. acidophilus in combination with isoflavone products may improve bone health in ovariectomized rats, warranting further research to elucidate potential interactions with other nutrients.

MOTS-c regulates pancreatic alpha and beta cell functions in vitro.

The aim of this study is to determine the influence of the mitochondrial open-reading-frame of the twelve S rRNA-c (MOTS-c) peptide on pancreatic cell physiology. Moreover, in this study, we examined the changes in MOTS-c secretion and expression under different conditions. Our experiments were conducted using laboratory cell line cultures, specifically the INS-1E and αTC-1 cell lines, which represent ß and α pancreatic cells, respectively. As the pancreas is an endocrine organ, we also tested its hormone regulation capabilities. Furthermore, we assessed the secretion of MOTS-c after incubating the cells with glucose and free fatty acids. Additionally, we examined key cell culture parameters such as cell viability, proliferation, and apoptosis. The results obtained from this study show that MOTS-c has a significant impact on the physiology of pancreatic cells. Specifically, it lowers insulin secretion and expression in INS-1E cells and enhances glucagon secretion and expression in αTC-1 cells. Furthermore, MOTS-c affects cell viability and apoptosis. Interestingly, insulin and glucagon affect the MOTS-c secretion as well as glucose and free fatty acids. These experiments clearly show that MOTS-c is an important regulator of pancreatic metabolism, and there are numerous properties of MOTS-c yet to be discovered.

Corrigendum to "Isoflavones and probiotics effect on bone calcium and bone cells in rats" [Heliyon 9(6) (June 2023) e16801].

[This corrects the article DOI: 10.1016/j.heliyon.2023.e16801.].

GIP_HUMAN [22-51] Peptide Encoded by the Glucose-Dependent Insulinotropic Polypeptide (GIP) Gene Suppresses Insulin Expression and Secretion in INS-1E Cells and Rat Pancreatic Islets.

GIP_HUMAN [22-51] is a recently discovered peptide that shares the same precursor molecule with glucose-dependent insulinotropic polypeptide (GIP). In vivo, chronic infusion of GIP_HUMAN [22-51] in ApoE-/- mice enhanced the development of aortic atherosclerotic lesions and upregulated inflammatory and proatherogenic proteins. In the present study, we evaluate the effects of GIP_HUMAN [22-51] on insulin mRNA expression and secretion in insulin-producing INS-1E cells and isolated rat pancreatic islets. Furthermore, we characterize the influence of GIP_HUMAN [22-51] on cell proliferation and death and on Nf-kB nuclear translocation. Rat insulin-producing INS-1E cells and pancreatic islets, isolated from male Wistar rats, were used in this study. Gene expression was evaluated using real-time PCR. Cell proliferation was studied using a BrdU incorporation assay. Cell death was quantified by evaluating histone-complexed DNA fragments. Insulin secretion was determined using an ELISA test. Nf-kB nuclear translocation was detected using immunofluorescence. GIP_HUMAN [22-51] suppressed insulin (Ins1 and Ins2) in INS-1E cells and pancreatic islets. Moreover, GIP_HUMAN [22-51] promoted the translocation of NF-κB from cytoplasm to the nucleus. In the presence of a pharmacological inhibitor of NF-κB, GIP_HUMAN [22-51] was unable to suppress Ins2 mRNA expression. Moreover, GIP_HUMAN [22-51] downregulated insulin secretion at low (2.8 mmol/L) but not high (16.7 mmol/L) glucose concentration. By contrast, GIP_HUMAN [22-51] failed to affect cell proliferation and apoptosis. We conclude that GIP_HUMAN [22-51] suppresses insulin expression and secretion in pancreatic ß cells without affecting ß cell proliferation or apoptosis. Notably, the effects of GIP_HUMAN [22-51] on insulin secretion are glucose-dependent.

Cord Blood Spexin Level in Mothers with Obesity-Forecast of Future Obesity?

Spexin (SPX) is a peptide that plays an important role in the regulation of food intake and body weight (BW) by the effect on carbohydrate-lipid metabolism. However, the role of SPX in fetal life, in children, and in adolescent metabolism is limited. Therefore, we decided to check whether obesity affects the concentration of SPX in the mother's peripheral blood (MB) and umbilical cord blood (UCB). Using MB and UCB sera on the day of delivery obtained from 48 women (24 non-obese and 24 obese) and commercially available Elisa kits and colorimetric assays, we determined changes in SPX and the relationship between SPX concentration and other metabolic and anthropometric markers (body weight and BMI) on the day of delivery and in children at the age of 36 months. We found lower concentrations of SPX in MB (p < 0.05) and UCB (p < 0.01) derived from obese women (BMI > 30) and a moderate linear correlation (r = 0.4429; p < 0.01) between SPX concentrations in MB and UCB. We also noted that the concentration of SPX is not correlated with the child's body weight on the day of birth (r = -0.0128). However, there is a relationship between SPX at birth and body weight at 3 years of age (r = -0.3219; p < 0.05). Based on the obtained results, it can be assumed that spexin is one of the factors modulating the child's metabolism already in the fetal period and can be considered a potential marker of future predisposition to obesity. However, confirmation of this thesis requires additional research.

Sex-specific cytotoxicity of ostarine in cardiomyocytes.

Ostarine is the most popular compound in the selective androgen receptor modulator group (SARMs). Ostarine is used as a physical performance-enhancing agent. The abuse of this agent in higher doses may lead to severe side effects. Here, we evaluate the effects of ostarine on the heart. We utilized a cardiomyocyte H9C2 cell line, isolated primary female and male cardiac fibroblast cells, as well as hearts obtained from rats. Ostarine increased the accumulation of two fibrosis protein markers, αSMA and fibronectin (p < 00.1) in male, but not in female fibroblast cells. Ostarine increased the expression of the cardiomyopathy marker ßMhc in the H9C2 cell line (p < 0.05) and in the heart in rats (p < 0.01). The unfavorable changes were observed at high ostarine doses. Moreover, a decrease in viability and an increase in cytotoxicity marker LDH were observed already at lowest dose (1 nmoL/l). Taken together, our results suggest that ostarine is cardiotoxic which may be more relevant in males than in females.

Isoflavones and probiotics effect on bone calcium and bone cells in rats.

Isoflavones and probiotics have shown the therapeutic potential to alter calcium absorption and bone cell metabolism. This study sought to ascertain the effect of isoflavones and probiotics on calcium status and bone health in healthy female rats. Forty-eight adult female Wistar rats were grouped and fed: a standard diet (control); and standard diets with tempeh; soy; daidzein and genistein; Lactobacillus acidophilus; and a combination of daidzein, genistein, and L. acidophilus. The biochemical serum parameters, such as alanine transaminase, aspartate transaminase, glucose, and triacylglycerol concentrations, were measured, and calcium contents in tissues were determined. After staining the bone with hematoxylin and eosin, the number of osteoblasts, osteocytes, and the percentage of bone marrow adipocytes were counted. Compared with the control group, the soy group showed a significantly lower triacylglycerol concentration. The L. acidophilus group considerably increased the calcium content in the femoral bone. The daidzein and genistein, L. acidophilus, and a combination of daidzein, genistein, and L. acidophilus groups showed significantly lower calcium contents in the heart and kidneys. The daidzein and genistein group significantly enhanced the number of osteoblasts and osteocytes. A substantial inverse correlation was observed between calcium contents in kidneys and osteoblasts. In conclusion, the combination of daidzein, genistein, and L. acidophilus may improve bone calcium concentrations and bone cells. However, no synergistic effect between isoflavones and probiotics was detected in this study.

DNA hypermethylation of Kiss1r promoter and reduction of hepatic Kiss1r in female rats with type 2 diabetes.

Kisspeptin, produced from the brain and peripheral tissues, may constitute an important link in metabolic regulation in response to external cues, such as diet. The kisspeptin system is well described in the brain. However, its function and regulation in the peripheral tissues, especially in relation to metabolic disease and sex differences, remain to be elucidated. As Kiss1 and Kiss1r, encoding for kisspeptin and kisspeptin receptors, respectively, are altered by overnutrition/fasting and regulated by DNA methylation during puberty and cancer, epigenetic mechanisms in metabolic disorders are highly probable. In the present study, we experimentally induced type 2 diabetes mellitus (DM2) in female Wistar rats using high-fat diet/streptozocin. We analysed expression and DNA methylation of Kiss1 and Kiss1r in the peripheral tissues, using quantitative-reverse-transcription PCR (qRT-PCR) and pyrosequencing. We discovered differential expression of Kiss1 and Kiss1r in peripheral organs in DM2 females, as compared with healthy controls, and the profile differed from patterns reported earlier in males. DM2 in females was linked to the increased Kiss1 mRNA in the liver and increased Kiss1r mRNA in the liver and adipose tissue. However, Kiss1r promoter was hypermethylated in the liver, suggesting gene silencing. Indeed, the increase in DNA methylation of Kiss1r promoter was accompanied by a reduction in Kiss1r protein, implying epigenetic or translational gene repression. Our results deliver novel evidence for tissue-specific differences in Kiss1 and Kiss1r expression in peripheral organs in DM2 females and suggest DNA methylation as a player in regulation of the hepatic kisspeptin system in DM2.

Effects of Calcium Lactate-Enriched Pumpkin on Calcium Status in Ovariectomized Rats.

This study aimed to evaluate the effects of enriched pumpkin on calcium status in ovariectomized rats. The study was conducted in sixty female Wistar rats, which were divided into six groups: a group fed a standard diet (C) and five ovariectomized groups fed a standard diet (OVX_C) or a diet with calcium lactate (CaL), with calcium lactate-enriched pumpkin (P_CaL), with calcium lactate and alendronate (CaL_B), or with calcium lactate-enriched pumpkin with alendronate (P_CaL_B). After 12 weeks of the intervention, the rats were sacrificed, and their blood and tissues were collected. The calcium concentrations in serum and in tissues were measured using flame atomic absorption spectrometry (AAS). Serum concentrations of procollagen type-1 amino-terminal propeptide (PINP), parathyroid hormone PTH, estrogen (ES), and osteocalcin (OC) were determined with enzyme-linked immunosorbent assay (ELISA). It was found that enriched pumpkin increased the calcium level in the kidneys (194.13 ± 41.01 mg) compared to the C (87.88 ± 12.42 mg) and OVX_C (79.29 ± 7.66 mg) groups. The addition of alendronate increased the calcium level in the femurs (267.63 ± 23.63 mg) and more than six times in the kidneys (541.33 ± 62.91 mg) compared to the OVX_C group (234.53 ± 21.67 mg and 87.88 ± 12.42 mg, respectively). We found that the CaL, P_CaL, and CaL_B groups had significantly lower PINP serum concentrations (4.45 ± 0.82 ng/mL, 4.14 ± 0.69 ng/mL, and 3.77 ± 0.33 ng/mL) and higher PTH serum levels (3.39 ± 0.54 ng/dL, 3.38 ± 0.57 ng/dL, and 3.47 ± 0.28 ng/dL) than the OVX_C group (4.69 ± 0.82 ng/mL and 2.59 ± 0.45 ng/dL, respectively). In conclusion, pumpkin enriched with calcium lactate affects calcium status and normalizes PINP and PTH serum levels in ovariectomized rats. Diet with enriched pumpkin and alendronate increase calcium concentration in the femur. Enriched pumpkin causes calcium to accumulate in the kidneys of ovariectomized rats; alendronate significantly exacerbates this effect.

Ostarine-Induced Myogenic Differentiation in C2C12, L6, and Rat Muscles.

Ostarine (also known as enobosarm or Gtx-024) belongs to the selective androgen receptor modulators (SARMs). It is a substance with an aryl-propionamide structure, classified as a non-steroidal compound that is not subjected to the typical steroid transformations of aromatization and reduction by α5 reductase. Despite ongoing research on ostarine, knowledge about it is still limited. Earlier studies indicated that ostarine may affect the metabolism of muscle tissue, but this mechanism has not been yet described. We aimed to investigate the effect of ostarine on the differentiation and metabolism of muscle. Using C2C12 and L6 cells, as well as muscles obtained from rats administered ostarine, we showed that ostarine stimulates C2C12 and L6 proliferation and cell viability and that this effect is mediated by androgen receptor (AR) and ERK1/2 kinase activation (p < 0.01). We also found that ostarine stimulates muscle cell differentiation by increasing myogenin, MyoD, and MyH expression in both types of cells (p < 0.01). Moreover, pharmacological blocking of AR inhibits the stimulatory effect of ostarine. We further demonstrated that 30 days of ostarine administration increases myogenin, MyoD, and MyH expression, as well as muscle mass, in rats (p < 0.01). Based on our research, we conclude that ostarine stimulates muscle tissue proliferation and differentiation via the androgen receptor.

Changes in metabolic and hormonal profiles during transition period in dairy cattle - the role of spexin.

BACKGROUND: This study aimed to evaluate spexin as a novel blood marker and to describe the relationship of this peptide with selected biochemical metabolites measured during the transition period in dairy cows. Additionally, mRNA expression of the spexin gene as well as spexin receptors - galanin receptor type 2 and galanin receptor type 3, was investigated in several bovine tissues. Blood samples were collected at weekly intervals starting at 21 days before the estimated parturition day until 21 days in milk to determine concentrations of spexin, nonesterified fatty acids, ß-hydroxybutyrate acid, total and active ghrelin, progesterone, glucose, insulin, IGF-I, triglycerides, cholesterol, leptin, corticosterone and 17-ß-estradiol as well as the activity of aspartate transaminase, alkaline phosphatase and gamma-glutamyl transferase. RESULTS: Spexin concentration decreased from 21 d before parturition to calving day and next it rose during the first 14 d of lactation. The lowest concentration of spexin was recorded on the calving day and it differed from the mean level of this peptide before parturition as well as postpartum. Moreover, differences were observed between mean spexin concentrations before and after calving. Spexin levels were moderately negatively correlated with NEFA (r = - 0.39) and total ghrelin contents (r = - 0.41), weakly correlated with BHBA (r = - 0.35) while they showed a moderate positive relationship with progesterone concentrations (r = 0.42). Moreover, we detected that mRNA expression of GALR2, GALR3 and SPX is present in various bovine tissues (kidney, bowel, rumen, spinal cord, lung, skeletal muscle, liver, heart, fat and spleen). CONCLUSION: A negative correlation between spexin concentration and NEFA, BHBA and total ghrelin contents as well as a positive relationship with levels of progesterone, metabolites and hormones, which are key players in the dairy cow transition period, may confirm an important function of this peptide in metabolism regulation. Thus measurement of spexin concentration could provide useful supplementary information for dairy cow herd health monitoring.

Changes in MOTS-c Level in the Blood of Pregnant Women with Metabolic Disorders.

MOTS-c peptide is a member of the group of mitochondria-derived peptides (MDP). It is a product of the open reading frame in the 12S RNA gene. Due to its features and functions in the body, this peptide is classified as a hormone. The first publications indicated that this hormone improves insulin sensitivity and lowers body weight in obese animals. This suggests that it may be an important peptide in maintaining the body's energy homeostasis. The aim of our work was to investigate the potential role of MOTS-c peptide during pregnancy, which is a condition prone to metabolic disorders. The research covered healthy, obese women and women with thyroid disorders. The obtained results indicated an increase in the concentration of MOTS-c in the blood of mothers and newborns in the obese group as compared to the healthy control group and a corresponding decrease in the concentration of this peptide in mothers and newborns in the group with hypothyroidism compared to the obese group. Moreover, we also observed a strong positive correlation between the concentration of MOTS-c in maternal blood and in umbilical cord blood. In summary, the MOTS-c peptide shows changes in blood concentration in various physiological states and may, in the future, become an important tool in the fight against metabolic diseases such as obesity or type 2 diabetes.

30-Day spexin treatment of mice with diet-induced obesity (DIO) and type 2 diabetes (T2DM) increases insulin sensitivity, improves liver functions and metabolic status.

Spexin (SPX) is a 14 aa peptide discovered in 2007 using bioinformatics methods. SPX inhibits food intake and regulates lipid, and carbohydrate metabolism. Here, we evaluate the ability of SPX at improving metabolic control and liver function in obese and type 2 diabetic animals. The effects of 30 days SPX treatment of mice with experimentally induced obesity (DIO) or type 2 diabetes (T2DM) on serum glucose and lipid levels, insulin sensitivity and hormonal profile (insulin, glucagon, adiponectin, leptin, TNF alpha, IL-6 and IL-1ß) are characterized. In addition, alterations of hepatic lipid and glycogen contents are evaluated. We report that SPX decreases body weight in healthy and DIO mice, and reduces lipid content in all three animal groups. SPX improves insulin sensitivity in DIO and T2DM animals. In addition, SPX modulates hormonal and metabolic profile by regulating the concentration of adiponectin (concentration increase) and leptin (concentration decrease) in the serum blood of DIO and T2DM mice. Lastly, SPX decreases lipid content as well as IL-6 and TNF-α protein levels in liver of DIO and T2DM mice, and reduces IL-6 and TNF-alpha concentrations in the serum derived from T2DM mice. Based on our results, we conclude that SPX could be involved in the development of obesity and type 2 diabetes mellitus and it can be further evaluated as a potential target for therapy of DIO and T2DM.

The Role of Peptide Hormones Discovered in the 21st Century in the Regulation of Adipose Tissue Functions.

Peptide hormones play a prominent role in controlling energy homeostasis and metabolism. They have been implicated in controlling appetite, the function of the gastrointestinal and cardiovascular systems, energy expenditure, and reproduction. Furthermore, there is growing evidence indicating that peptide hormones and their receptors contribute to energy homeostasis regulation by interacting with white and brown adipose tissue. In this article, we review and discuss the literature addressing the role of selected peptide hormones discovered in the 21st century (adropin, apelin, elabela, irisin, kisspeptin, MOTS-c, phoenixin, spexin, and neuropeptides B and W) in controlling white and brown adipogenesis. Furthermore, we elaborate how these hormones control adipose tissue functions in vitro and in vivo.

The Long-Term Effects of High-Fat and High-Protein Diets on the Metabolic and Endocrine Activity of Adipocytes in Rats.

The increasing prevalence of overweight and obesity and the rising awareness of their negative consequences are forcing researchers to take a new view of nutrition and its consequences for the metabolism of whole organisms as well as the metabolism of their individual systems and cells. Despite studies on nutrition having been carried out for a few decades, not many of them have focused on the impacts of these diets on changes in the metabolism and endocrine functions of isolated adipocytes. Therefore, we decided to investigate the effects of the long-term use (60 and 120 days) of a high-fat diet (HFD) and of a high-protein diet (HPD) on basic metabolic processes in fat cells-lipogenesis, lipolysis, and glucose uptake-and endocrine function, which was determined according to the secretion of adipokines into the incubation medium. Our results proved that the HPD diet improved insulin sensitivity, increased the intracellular uptake of glucose (p < 0.01) and its incorporation into lipids (p < 0.01) and modulated the endocrine function of these cells (decreasing leptin secretion; p < 0.01). The levels of biochemical parameters in the serum blood also changed in the HPD-fed rats. The effects of the HFD were inverse, as expected. We observed a decrease in adiponectin secretion and a diminished rate of lipogenesis (p < 0.01). Simultaneously, the secretion of leptin and resistin (p < 0.01) from isolated adipocytes increased. In conclusion, we noted that the long-term use of HPD and HFD diets modulates the metabolism and endocrine functions of isolated rat adipocytes. We summarize that an HFD had a negative effect on fat tissue functioning, whereas an HPD had positive results, such as increased insulin sensitivity and an improved metabolism of glucose and lipids in fat tissue. Moreover, we noticed that negative metabolic changes are reflected more rapidly in isolated cells than in the metabolism of the whole organism.

Resveratrol Affects Insulin Signaling in Type 2 Diabetic Goto-Kakizaki Rats.

Resveratrol is a biologically active diphenolic compound exerting multiple beneficial effects in the organism, including anti-diabetic properties. This action is, however, not fully elucidated. In the present study, we examined effects of resveratrol on some parameters related to insulin signaling, and also on diabetes-associated dysregulation in Goto-Kakizaki (GK) rats with congenital type 2 diabetes. Resveratrol was given at the dose of 20 mg/kg b.w. for 10 weeks. It was shown that the expression and phosphorylation levels of insulin receptor in the skeletal muscle of GK rats were significantly decreased, compared with control animals. However, these changes were totally prevented by resveratrol. Liver expression of the insulin receptor was also reduced, but in this case, resveratrol was ineffective. Resveratrol was also demonstrated to significantly influence parameters of insulin binding (dissociation constant and binding capacity) in the skeletal muscle and liver. Moreover, it was shown that the expression levels of proteins related to intracellular glucose transport (GLUT4 and TUG) in adipose tissue of GK rats were significantly decreased. However, treatment with resveratrol completely abolished these changes. Resveratrol was found to induce normalization of TUG expression in the skeletal muscle. Blood levels of insulin and GIP were elevated, whereas proinsulin and GLP-1 diminished in GK rats. However, concentrations of these hormones were not affected by resveratrol. These results indicate that resveratrol partially ameliorates diabetes-associated dysregulation in GK rats. The most relevant finding covers the normalization of the insulin receptor expression in the skeletal muscle and also GLUT4 and TUG in adipose tissue.

Effect of Fasting on the Spexin System in Broiler Chickens.

Spexin (SPX) is a highly conservative peptide hormone containing 14 amino acids and was discovered in 2007 by bioinformatics methods. However, nothing is yet known about its role in the metabolism of birds, including broilers. The aim of this study was to investigate the effect of short-term fasting (2, 4, and 8 h) on the concentration of SPX in blood serum and the expression levels of the genes encoding this peptide (SPX1) and its receptors, GALR2 and GALR3, in the tissues involved in carbohydrate and lipid metabolism (muscles, adipose tissue, and liver). We also analyzed the mRNA expression of these genes in various chicken tissues. Moreover, we studied the correlation between the serum level of SPX and other metabolic parameters (insulin, glucagon, glucose, triglycerides, and cholesterol). Using RT-qPCR, we found that SPX1, GALR2, and GALR3 are expressed in all investigated tissues in broiler chicken. Moreover, using a commercially available radio-immunoassay, we noted an increase of the SPX level in blood serum after 4 and 8 h of fasting compared to nonfasted animals (p < 0.05). This increase was positively correlated with glucagon concentration (r = 0.341; p < 0.05) and negatively with glucose concentration (r = -0.484; p < 0.01). Additionally, we discovered that in the short term, food deprivation leads to the expression regulation of SPX1, GALR2, and GLAR3 in tissues associated with metabolism of carbohydrates and lipids. The obtained results indicate that SPX is involved in the regulation of metabolism in broiler chickens.

Transcriptome Changes in Three Brain Regions during Chronic Lithium Administration in the Rat Models of Mania and Depression.

Lithium has been the most important mood stabilizer used for the treatment of bipolar disorder and prophylaxis of manic and depressive episodes. Despite long use in clinical practice, the exact molecular mechanisms of lithium are still not well identified. Previous experimental studies produced inconsistent results due to different duration of lithium treatment and using animals without manic-like or depressive-like symptoms. Therefore, we aimed to analyze the gene expression profile in three brain regions (amygdala, frontal cortex and hippocampus) in the rat model of mania and depression during chronic lithium administration (2 and 4 weeks). Behavioral changes were verified by the forced swim test, open field test and elevated maze test. After the experiment, nucleic acid was extracted from the frontal cortex, hippocampus and amygdala. Gene expression profile was done using SurePrint G3 Rat Gene Expression whole transcriptome microarrays. Data were analyzed using Gene Spring 14.9 software. We found that chronic lithium treatment significantly influenced gene expression profile in both mania and depression models. In manic rats, chronic lithium treatment significantly influenced the expression of the genes enriched in olfactory and taste transduction pathway and long non-coding RNAs in all three brain regions. We report here for the first time that genes regulating olfactory and taste receptor pathways and long non-coding RNAs may be targeted by chronic lithium treatment in the animal model of mania.

Serum spexin concentration, body condition score and markers of obesity in dogs.

BACKGROUND: Spexin (SPX) is a peptide hormone that regulates body weight, adipose tissue metabolism, and food intake. HYPOTHESIS: Serum SPX concentration correlates with body condition score (BCS) and markers of obesity in dogs. ANIMALS: Fifty-seven dogs of varying body condition assessed using a 5-point BCS. METHODS: Prospective, nonblinded, observational cohort study. Serum SPX concentration was measured using commercially available radioimmunoassay (RIA) in dogs with varying BCS. Spexin mRNA and protein expression were detected using real-time quantitative polymerase chain reaction and immunofluorescence staining. RESULTS: Serum SPX concentration was lower in dogs with BCS4 (8.56 +/- 2.86) and BCS5 (6.7 +/- 2.12) compared to BCS2 (11.96 +/- 2.23) and BCS3 (10.51 +/- 2.19; BCS2 vs BCS5, P < .001 and BCS2 vs BCS4, P = .005; BCS3 vs BCS5, P = .002). Spexin mRNA was detected in adipose tissue, liver and pancreas. Spexin protein was expressed in adipose tissue and liver but not in pancreas. There were negative correlations between SPX and serum concentration of insulin (P < .05); leptin (P < .01), triglycerides (P < .01), total cholesterol (P < .01), nonesterified fatty acids (P < .01), and fructosamine (P < .01). There was a positive correlation between SPX and serum concentration of adiponectin (P < .01). CONCLUSIONS AND CLINICAL IMPORTANCE: Spexin could be involved in pathogenesis of obesity in dogs, and might be considered as a potential marker for obesity.

Spexin Promotes the Proliferation and Differentiation of C2C12 Cells In Vitro-The Effect of Exercise on SPX and SPX Receptor Expression in Skeletal Muscle In Vivo.

SPX (spexin) and its receptors GalR2 and GalR3 (galanin receptor subtype 2 and galanin receptor subtype 3) play an important role in the regulation of lipid and carbohydrate metabolism in human and animal fat tissue. However, little is still known about the role of this peptide in the metabolism of muscle. The aim of this study was to determine the impact of SPX on the metabolism, proliferation and differentiation of the skeletal muscle cell line C2C12. Moreover, we determined the effect of exercise on the SPX transduction pathway in mice skeletal muscle. We found that increased SPX, acting via GalR2 and GalR3 receptors, and ERK1/2 phosphorylation stimulated the proliferation of C2C12 cells (p < 0.01). We also noted that SPX stimulated the differentiation of C2C12 by increasing mRNA and protein levels of differentiation markers Myh, myogenin and MyoD (p < 0.01). SPX consequently promoted myoblast fusion into the myotubule (p < 0.01). Moreover, we found that, in the first stage (after 2 days) of myocyte differentiation, GalR2 and GalR3 were involved, whereas in the last stage (day six), the effect of SPX was mediated by the GalR3 isoform. We also noted that exercise stimulated SPX and GalR2 expression in mice skeletal muscle as well as an increase in SPX concentration in blood serum. These new insights may contribute to a better understanding of the role of SPX in the metabolism of skeletal muscle.