Zhenqing recipe relieves diabetic nephropathy through the SIK1/SREBP-1c axis in type 2 diabetic rats.

BACKGROUND: Salt-inducible kinase 1 (SIK1) plays an important role in lipid metabolism, which inhibits lipid synthesis by directly phosphorylating multiple serine residue sites of sterol regulatory element-binding protein 1c (SREBP-1c). This study examined potential therapeutic effect of a Chinese herbal medicine Zhenqing Recipe (ZQR) and metformin on diabetic nephropathy and investigated whether the SIK1/SREBP-1c axis is involved. METHODS: The rat model of type 2 diabetes was developed by high-sucrose plus high fat diet for one month combined with low-dose Streptozocin intraperitoneal injection for three days, after which the presence of hyperglycemia and hyperlipidemia was examined to validate the model. The diabetic rats were then randomly allocated to diabetic groups treated by either ZQR or metformin, and normal rats receiving normal diet were included as a control group. Metabolic parameters, renal function, and renal triglyceride were examined and compared between groups. RESULTS: After a treatment of 12 weeks, ZQR and metformin significantly reduced serum glucose and triglyceride, inhibited diabetic nephropathy and improved renal function. The mRNA level of SIK1 was significantly lower in the diabetic rats than that in the control group, while the expression of SREBP-1c had an opposite pattern. However, after receiving ZQR or metformin treatment, the SIK1 level in diabetic rats increased and the SREBP-1c level was downregulated. Consistent results were observed at the protein level. CONCLUSION: The data suggested that similar to metformin, ZQR could alleviate diabetic nephropathy through SIK1/SREBP-1c axis.

SIK1 Regulates CRTC2-Mediated Gluconeogenesis Signaling Pathway in Human and Mouse Liver Cells.

The regulation of hepatic gluconeogenesis is of great significance to improve insulin resistance and benefit diabetes therapy. cAMP-Regulated Transcriptional Co-activator 2 (CRTC2) plays a key role in regulating hepatic gluconeogenesis through controlling the expression of gluconeogenic rate-limiting enzymes such as glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK). Recently, salt-inducible kinase 1 (SIK1) has been identified to play an important role in glucose metabolism disorders, but whether and how SIK1 regulates the CTRC2 signaling in liver cells under high glucose conditions has rarely been intensively elucidated. Here, we show that high glucose stimulation resulted in time-dependent down-regulated expression of SIK1, phosphorylated SIK1 at T182 site, and phosphorylated CRTC2 at S171 site, as well as upregulated expression of total CRTC2 and its downstream targets G6Pase and PEPCK in the human liver cell line HepG2. The nuclear expression levels of SIK1 and CRTC2 were time-dependently upregulated upon high glucose challenge, which was accompanied by enhanced cytoplasm-to-nucleus translocation of SIK1. Manipulation of SIK1 activity using plasmid-mediated SIK1 over-expression and the use of the SIKs inhibitor HG-9-91-01 confirmed that SIK1 regulated the CRTC2 signaling pathway in HepG2 cells. Furthermore, in mouse primary hepatocytes, high glucose exposure down-regulated SIK1 expression, and promoted SIK1 nuclear accumulation. While HG-9-91-01 treatment suppressed SIK1 expression and released the inhibitory effects of SIK1 on the expressions of key molecules involved in the CRTC2 signaling pathway, additional ectopic expression of SIK1 using adenovirus infection reversed the impacts of HG-9-91-01 on the expressions of these molecules in mouse hepatocytes. Therefore, SIK1 regulates CRTC2-mediated gluconeogenesis signaling pathway under both physiological and high glucose-induced pathological conditions. The modulation of the SIK1-CRTC2 signaling axis could provide an attractive means for treating diabetes.

Zhenqing recipe attenuates non-alcoholic fatty liver disease by regulating the SIK1/CRTC2 signaling in experimental diabetic rats.

BACKGROUND: As a compound Chinese medicine, Zhenqing Recipe (ZQR) has been shown to ameliorate hyperglycemia, hyperlipidemia, fatty liver and insulin resistance in patients with diabetes and diabetic rats. In this paper, we further examined the effect of ZQR on diabetes complicated by non-alcoholic fatty liver disease (NAFLD) and the underlying molecular mechanisms. METHODS: Diabetic rats with NAFLD were developed by a high-fat diet (HFD) with low-dose streptozotocin (STZ) injection for 4 weeks. These rats were randomly separated into the diabetic model (DM), ZQR, metformin (Met), adenovirus expressing-salt-induced kinase 1 (Ad-SIK1) and adenovirus labeled with green fluorescent protein (Ad-GFP) groups. The effects on hepatic expression of gluconeogenic genes, glycolipid metabolism and pathological changes were subsequently detected. RESULTS: Serum glucose, triglycerides (TG), total cholesterol (TC) and hepatic TG were reduced in the ZQR group. The histopathological and immunohistochemical changes in the liver and pancreas in the ZQR group were significantly alleviated. The decrease of SIK1 expression was observed in the liver of diabetic rats induced by HFD and STZ. SIK1 overexpression in the liver relieved hyperglycemia, hyperlipidemia and fatty liver. Both the mRNA and protein levels of CREB-regulated transcription co-activator 2 (CRTC2), phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) in the liver were drastically reduced, whereas those of SIK1 were markedly increased in the ZQR group compared to levels in the DM group. Compared with the DM group, Ser577 phosphorylation of SIK1 was obviously reduced in the liver, while T182 phosphorylation of SIK1 and S171 phosphorylation of CRTC2 were evidently increased in the Ad-SIK1, Met and ZQR groups. CONCLUSIONS: ZQR ameliorates hepatic gluconeogenesis and lipid storage in diabetic rats induced by HFD and STZ by activating the SIK1/CRTC2 signaling pathway. Upregulating hepatic SIK1 by ZQR may represent an efficient strategy for treating diabetes with NAFLD.

Adenovirus-mediated expression of SIK1 improves hepatic glucose and lipid metabolism in type 2 diabetes mellitus rats.

AIM: In this study, we investigated the role and mechanism of Salt-induced kinase 1 (SIK1) in regulation of hepatic glucose and lipid metabolism in a high-fat food (HFD) and streptozocin (STZ)-induced type 2 diabetes mellitus (T2DM) rat model. METHODS: A diabetic rat model treated with HFD plus low-dose STZ was developed and was transduced to induce a high expression of SIK1 in vivo via a tail-vein injection of a recombinant adenoviral vector. The effects on hepatic glucogenetic and lipogenic gene expression, systemic metabolism and pathological changes were then determined. RESULTS: In T2DM rats, SIK1 expression was reduced in the liver. Overexpression of SIK1 improved hyperglycaemia, hyperlipidaemia and fatty liver, reduced the expression of cAMP-response element binding protein (CREB)-regulated transcription co-activator 2 (CRTC2), phosphoenolpyruvate carboxykinase (PEPCK), glucose-6-phosphatase (G6Pase), pS577 SIK1, sterol regulatory element binding-protein-1c (SREBP-1c) and its target genes, including acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS), and increased the expression of SIK1, pT182 SIK1 and pS171 CRTC2 in diabetic rat livers with the suppression of gluconeogenesis and lipid deposition. CONCLUSION: SIK1 plays a crucial role in the regulation of glucose and lipid metabolism in the livers of HFD/STZ-induced T2DM rats, where it suppresses hepatic gluconeogenesis and lipogenesis by regulating the SIK1/CRTC2 and SIK1/SREBP-1c signalling pathways. Strategies to activate SIK1 kinase in liver would likely have beneficial effects in patients with T2DM and nonalcoholic fatty liver disease (NAFLD).

Jueming prescription and its ingredients, semen cassiae and Rhizoma Curcumae Longae, stimulate lipolysis and enhance the phosphorylation of hormone­sensitive lipase in cultured rat white adipose tissue.

The present study aimed to investigate the effect of jueming prescription (JMP) and its ingredients, semen cassiae (SC) and Rhizoma Curcumae Longae (RCL), on lipolysis, and to examine their effect on the phosphorylation of hormone­sensitive lipase (HSL) in cultured rat white adipose tissue (WAT). Retroperitoneal WAT was aseptically excised from adult male Sprague­Dawley rats, minced into uniform sections and subjected to ex vivo culture for 24 h. The tissue sections were then distributed into a 24­well culture plate and treated with normal saline (vehicle), isoproterenol (ISO), JMP, SC and RCL. Non­esterified fatty acid (NEFA) and glycerol release from the intact WAT explants were determined as a measurement of lipolysis, which were measured using NEFA and glycerol assay kits. The phosphorylation of HSL at Ser563 (P­HSL S563) and 660 residues (P­HSL S660) were determined using western blot analysis. The size of the adipocytes was visualized using hematoxylin and eosin (H&E) staining. It was found that JMP­, SC­ and RCL­stimulated lipolysis was responsible for increasing the release of NEFAs and glycerol from the intact WAT in vitro. In addition, JMP, SC and RCL increased the levels of P­HSL Ser563: JMP water (JW) extract, 3.52­fold; JMP ethanol (JE) extract, 3.38­fold; SC water (SW) extract, 4.60­fold; SC ethanol (SE) extract, 4.20­fold; RCL water (RW) extract, 6.98­fold; RCL ethanol (RE) extract, 6.60­fold. JMP, SC and RCL also increased the levels of P­HSL Ser660: JW extract, 3.16­fold; JE extract, 2.92­fold; SW extract, 4.57­fold; SE extract, 4.13­fold; RW extract, 5.41­fold; RE 4.96­fold) in the WAT. The RW extract had the most marked effect. The HE staining revealed that JMP, SC and RCL reduced the size of adipocytes in the WAT. In conclusion, JMP and its ingredients, SC and RC, stimulated lipolysis and reduced the size of adipocytes, possibly via the phosphorylation of HSL in cultured rat WAT.

Role of salt inducible kinase 1 in high glucose-induced lipid accumulation in HepG2 cells and metformin intervention.

AIMS: To investigate the roles of salt inducible kinase (SIK1) in high glucose-induced triglyceride accumulation in human hepatoma HepG2 cells as well as in the molecular mechanism by which metformin, a drug to treat diabetes, suppresses high glucose-induced lipogenesis. MAIN METHODS: A cell model for high glucose-induced hepatic steatosis was prepared by exposing HepG2 cells to high glucose (25mmol) in the absence or presence of metformin (0.5mmol). Intracellular triglycerides were visualized by Oil Red O and measured using a triglyceride assay kit. Cell viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. SIK1 overexpression in HepG2 cells was achieved by transient transfection, and the mRNA and protein levels of SIK1 and lipogenic factors were measured using a reverse transcription-polymerase chain reaction and western blotting, respectively. KEY FINDINGS: Lipid accumulation in HepG2 cells was obvious after treatment with high glucose for 24h. In response to high glucose, SIK1 expression was negatively correlated with that of lipogenic factors and lipid accumulation in HepG2 cells. We observed that overexpression of SIK1, or treatment with metformin, suppressed lipogenesis, even in high glucose conditions. Furthermore, treatment with metformin upregulated SIK1 mRNA and protein levels, as well as the active form of SIK1. SIGNIFICANCE: SIK1 plays a vital role in high glucose-induced lipid accumulation, and metformin suppresses lipogenesis via the induction and activation of SIK1.

[Effect of zhenqing recipe on non-alcoholic fatty liver in type 2 diabetes rats and the expression of SIK1].

OBJECTIVE: To observe the effect of Zhenqing Recipe (ZQR) on non-alcoholic fatty liver (NAFL), and the expression of hepatic salt-inducible kinase 1 (SIK1) and sterol-regulatory element binding protein-ic (SREBP-lc) in type 2 diabetes rats. METHODS: A rat model of type 2 diabetes was established by high fat/sucrose diet combined with intraperitoneal injection of small dose streptozotocin (STZ) . Modeled rats were randomly divided into the model group, the ZQR group, and the metformin group, 8 in each group. Eight rats were recruited as a normal control group. ZQR at the daily dose of 12 g crude drugs/kg was administered to rats in the ZQR group by gastrogavage. Metformin suspension at the daily dose of 150 mg/kg was administered to rats in the metformin group by gastrogavage. Equal volume of distilled water was administered to rats in the normal control group and the model group. All medication lasted for 12 weeks. The levels of fasting blood glucose (FBG), free fatty acid (FFA), serum triglyceride (TG), serum total cholesterol (TC), serum alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were detected. The body weight and wet liver weight were weighed, and the liver weight index calculated. The liver TG content was measured. The pathological changes of liver and the expression of SIK1 were observed by HE staining and immunohistochemistry. The mRNA and protein expression of SIK1 and SREBP-1c were detected using RT-PCR and Western blot. RESULTS: Compared with the normal control group, FBG, FFA, TG, TC, ALT, AST, liver weight index, and liver TG contents significantly increased (P < 0.01); liver steatosis was severe, the mRNA and protein expression of SIK1 obviously decreased (P < 0.01); mRNA and protein expression of SREBP-1c increased (P < 0.01). After drug therapy, compared with the model group, FBG, FFA, TG, TC, ALT, AST, and liver weight index significantly decreased, liver TG contents significantly decreased, the mRNA and protein expression of SIK1 obviously increased, while mRNA and protein expression of SREBP-1c obviously decreased (P < 0.05, P < 0.01) in the ZQR group and the metformin group (P < 0.05, P < 0.01); and the pathological changes were also improved. All the indices were improved more in the ZQR group (all P < 0.05). CONCLUSION: In this experiment, we found that the expression of SIK1 decreased in NAFL rats with type 2 diabetes. ZQR could alleviate lesion of NAFL type 2 diabetes rats possibly by up-regulating hepatic SIK1 expression at mRNA and protein levels.

Salt-inducible kinase 1 is involved in high glucose-induced mesangial cell proliferation mediated by the ALK5 signaling pathway.

High glucose levels can induce mesangial cell proliferation and extracellular matrix (ECM) accumulation through the type I activin receptor-like kinase 5 (ALK5) signaling pathway. Salt-inducible kinase 1 (SIK1) prevents fibrosis by downregulating ALK5, while the expression level of the SIK1 protein itself is downregulated by glucose in neuronal cells following ischemia. In this study, we investigated the correlation between SIK1 and the ALK5 signaling pathway in a rat glomerular mesangial cell line (HBZY-1 cells). We found that high glucose levels downregulated the expression level of SIK1 and suppressed the phosphorylation of SIK1 at Thr-182. The downregulation of SIK1 by high glucose was accompanied by the activation of the ALK5 signaling pathway, while the overexpression of SIK1 in the HBZY-1 cells resulted in a decrease in the ALK5 protein level, as well in the levels of its downstream targets, including fibronectin and plasminogen activator inhibitor type I. In conclusion, high glucose may activate the ALK5 signaling pathway by downregulating SIK1, and SIK1 may be a protective factor against cellular proliferation and ECM accumulation in glomerular mesangial cells under high glucose conditions.

Zhenqing recipe improves glucose metabolism and insulin sensitivity by repressing hepatic FOXO1 in type 2 diabetic rats.

Forkhead box O1 (FOXO1) plays an important role in glucose metabolism at the gene transcription level. Increased FOXO1 activity results in hyperglycemia by promoting the expression of gluconeogenic enzymes such as phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase), and inhibiting glucokinase (GK). This study evaluates the effect of Zhenqing Recipe (ZQR), a Chinese herbal medicine, on hyperglycemia and its molecular mechanisms. Type 2 diabetic rats, developed by high-fat diet combined with low-dose STZ injections, were randomly divided into untreated diabetic, ZQR and metformin group. Normal rats served as control. After an eight-week treatment, fasting blood glucose was significantly decreased and insulin sensitivity index was obviously increased in the ZQR group. ZQR also improved the oral glucose tolerance. Compared with the control group, the mRNA levels of PEPCK and G6Pase were significantly elevated, while GK mRNA expression was decreased in the liver of untreated diabetic rats. ZQR significantly reduced the mRNA levels of PEPCK and G6Pase, and increased GK mRNA expression. The hepatic mRNA and protein expression of FOXO1 in the untreated diabetic group was markedly increased compared to controls. The administration of ZQR significantly decreased the mRNA and protein levels of hepatic FOXO1. The data suggest that ZQR improves glucose metabolism and insulin sensitivity, which is accompanied with regulating mRNA expression of GK and gluconeogenic genes. This anti-diabetic effect of ZQR is due to its ability to repress hepatic FOXO1 at the mRNA and protein level.

Zhenqing recipe alleviates diabetic nephropathy in experimental type 2 diabetic rats through suppression of SREBP-1c.

ETHNOPHARMACOLOGICAL RELEVANCE: Zhenqing Recipe (ZQR), a Chinese herbal prescription, is used to improve renal function of patients with diabetic nephropathy. In current research, the therapeutic effects of ZQR on type 2 diabetic nephropathy and the underlying molecular mechanisms were explored. MATERIALS AND METHODS: Animal model with diabetic nephropathy was developed by high fat/sucrose diet feeding plus streptozotocin injection for 4 weeks. The diabetic rats were then orally administered with ZQR extract at the dose of 4 g/kg, 8 g/kg body weight/day for 8 weeks. RESULTS: Serum glucose, triglyceride and total cholesterol in untreated diabetic rats were significantly higher than that of normal control rats. ZQR treatment not only reduced serum glucose level in diabetic rats, but also decreased serum triglyceride and total cholesterol in a dose-dependent manner. Urinary albumin excretion rate, serum urea and creatinine were significantly decreased in ZQR groups compared with untreated diabetic group. Histopathological study of kidney samples showed that extracellular mesangial matrix expansion in diabetic rats was suppressed by ZQR treatment. Both mRNA and protein levels of sterol regulatory element binding-protein-1c (SREBP-1c), and its target genes including acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) in renal cortex were significantly decreased in ZQR treated rats compared to untreated diabetic rats. Consequently, renal triglyceride was significantly reduced in ZQR groups. Furthermore, ZQR significantly inhibited the overexpression of transforming growth factor-ß1 and fibronectin in the renal cortex of diabetic rats. CONCLUSIONS: Oral treatment of ZQR improved diabetic nephropathy by inhibiting the overexpression of SREBP-1c and its target genes including ACC and FAS in experimental type 2 diabetic rats.

Jueming Prescription reduces body weight by increasing the mRNA expressions of beta3-adrenergic receptor and uncoupling protein-2 in adipose tissue of diet-induced obese rats.

OBJECTIVE: To investigate the antiobesity effect of Jueming Prescription (JMP), a Chinese herbal medicine formula, and its influence on mRNA expressions of beta3 adrenergic receptor (beta3-AR) and uncoupling protein-2 (UCP-2) in adipose tissue of diet-induced obese rats. METHODS: Fifty male Sprague-Dawley rats were randomly divided into the normal control group (n =8) that was on a standard chow diet, and the obese model group (n =42) that was on a diet of high fat chow. Two weeks after the high fat diet, 29 obese rats in the obese model group were further randomly divided into 3 groups: the untreated obese model group (n =9), the metformin group (n =10, metformin 300 mg kg⁻¹ day)⁻¹, and the JMP group (n =10, JMP 4 g kg⁻¹ day⁻¹). After 8-week treatment, body weight, wet weight of visceral fat, and percentage of body fat (PBF) were measured. The levels of fasting blood glucose, serum lipids, and insulin were assessed, and insulin sensitivity index (ISI) was calculated. The adipose tissue section was stained with hematoxylin-Eosin, and the cellular diameter and quantity of adipocytes were evaluated by light microscopy. The mRNA expressions of beta3-AR and UCP-2 from the peri-renal fat tissue were determined by real-time reverse transcription polymerase chain reaction (RT-PCR). RESULTS: Compared with the obese model group, treatment with JMP resulted in significantly lower body weight, wet weight of visceral fat, PBF, and diameter of adipocytes, and significantly higher level of high-density lipoprotein cholesterol, ISI (all P<0.01), JMP increased the mRNA expressions of beta3-AR and UCP-2 from perirenal fat tissue (P <0.05, P<0.01). CONCLUSIONS: JMP could reduce body weight and adipocyte size; and the effect was associated with the up-regulation of beta3-AR and UCP-2 expressions in the adipose tissue and improvement of insulin sensitivity.

[Effects of zhenqing recipe and earthworm on the expressions of transforming growth factor-beta1 and plasminogen activator inhibitor 1 in renal tissues of type 2 diabetic rats].

OBJECTIVE: To study the effects of Zhenqing Recipe (ZQR) and earthworm on the expressions of transforming growth factor-beta1 (TGF-beta1) and plasminogen activator inhibitor-1 (PAI-1) in renal tissues of type 2 diabetes mellitus (T2DM) rats. METHODS: The T2DM model rats induced by high sucrose/fat feeding and low dose streptozotocin injecting were randomly divided into the model group, the ZQR group, and the earthworm group. A normal control group was also set up. ZQR extract was given at the daily dose of 24 g/kg body weight by gastrogavage to rats in the ZQR group. The earthworm extract was given at the daily dose of 2.6 g/kg body weight by gastrogavage to rats in the earthworm group. Equal volume of distilled water was given to rats in the normal control group and the model group by gastrogavage. The medication was once daily for 8 successive weeks. The fasting blood glucose (FBG), serum PAI-1, 24-h urinary albumin excretion (UAE), and endogenous creatinine clearance rate (CCr) were detected. The structural changes of renal tissues stained with Periodic Acid-Schiff were observed by light microscope. The expressions of TGF-beta1 and PAI-1 were analyzed by immunohistochemistry. And the mRNA and protein expressions of TGF-beta1 and PAI-1 in the renal cortex were detected by Real-time PCR and Western blot respectively. RESULTS: Compared with the normal control group, the FBG, serum PAI-1, UAE, the mRNA and protein expressions of TGF-beta1, and PAI-1 significantly increased in the model group, and CCr obviously decreased (P<0.01). Compared with the model group, FBG, serum PAI-1, UAE obviously decreased (P<0.01) and CCr obviously increased (P<0.05) in the ZQR group. FBG was not obviously lowered in the earthworm group. The serum PAI-1 and UAE both decreased obviously (P<0.05, P<0.01) and CCr increased (P<0.05) in the earthworm group. The effects of ZQR were superior to the earthworm. The renal pathological changes got improved in the ZQR group and the earthworm group. The mRNA and protein expressions of TGF-beta1 and PAI-1 significantly decreased in the ZQR group and the earthworm group, especially in the ZQR group. CONCLUSIONS: Early application of ZQR and earthworm in treatment of T2DM rats with nephropathy was effective in protecting the kidney. Its mechanism may possibly be correlated with inhibition of TGF-beta1 expression, resulting in down-regulation of PAI-1 expression. ZQR showed better effects than earthworm.

[Amelioration effect of Zhenqing Capsule on peripheral neuropathy in type 1 diabetic rats].

OBJECTIVE: To investigate the effects of Zhenqing Capsule (ZQC), a compound traditional Chinese herbal medicine, in treating type 1 diabetic rats with peripheral neuropathy. METHODS: Type 1 diabetes was induced by caudal vein injection of high-dose streptozotocin in 30 male Wistar rats. The thirty diabetic rats were randomly divided into three groups: ZQC-treated group, untreated group and aminoguanidine-treated group. Another group of 10 rats was taken as normal control. After 10-week treatment, the changes of body weight and fasting plasma glucose level were measured, and the serum MDA level and the changes of neurological electrophysiology were analyzed. The samples of sciatic nerve in diabetic rats were taken for morphological observation. RESULTS: The MDA level in type 1 diabetic rats was notably reduced in ZQC-treated group as compared with the untreated group (P<0.01). Compared with the untreated group, ZQC could improve the electrophysiology of sciatic nerve including conduction velocity (P<0.05), latency (P<0.01) and wave amplitude (P<0.05). The nerve myelin staining results showed that segmental demyelination of the nerve fibers in ZQC-treated group was not as serious as that in the untreated group. CONCLUSION: ZQC can obviously ameliorate the neurological electrophysiological function and the pathological changes of peripheral nerve in type 1 diabetic rats through the removal of free radical and resistance of lipid peroxidation.

[Modulative effect of zhenqing recipe on expressions of matrix metalloproteinase-9 and tissue inhibitor of matrix metalloproteinase-1 in experimental type 2 diabetic rats].

OBJECTIVE: To explore the effect of Zhenqing Recipe (ZQR) on renal structure and expressions of matrix metalloproteinase-9 (MMP-9), tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) in experimental type 2 diabetic rats. METHODS: The rat models of type 2 diabetic were set up by intraperitoneally giving small-dose streptozotocin (STZ) after fed with high carbohydrate and high fat diets for one month. The model rats were randomly divided into the model group,the high and low dose ZQR-treated groups,and the enalapril-treated group; a normal control group was also established. The course of treatment continued 8 weeks. The expressions of MMP-9, TIMP-1, and fibronectin (FN) in renal tissues were detected by immunohistochemistry. The morphological changes of glomeruli and renal tubules were checked by microscopy. RESULTS: Compared with the normal control group, the expression of TIMP-1 and FN increased and MMP-9 decreased in the model group; the treated groups could decrease the expressions of TIMP-1 and FN, and increase the expression of MMP-9, especially the high-dose ZQR group had the best effect. The morphological changes of renal tubules and glomerulus in the treated groups were improved better as compared with the model group. CONCLUSION: The protective effect of ZQR on renal structure may be achieved by modulating the expressions of MMP-1 and TIMP-1.

A study of lipoprotein lipase gene intron 8 polymorphisms in Chinese Han race essential hypertension patients.

OBJECTIVE: To investigate the association of lipoprotein lipase gene intron 8 polymorphisms and Essential Hypertension in Han race Chinese. METHODS AND RESULTS: 116 patients with Essential Hypertension were enrolled and another 116 normal people were served as controls. All cases were examined for the genotypes of intron 8 in lipoprotein lipase gene by the methods of polymerase chain reaction restriction fragment length polymorphism, and the serum lipoprotein levels were also observed. Results showed that body mass index blood pressure and the serum triglyceride level were obviously increased in the Essential Hypertension group. The genotype and allele frequency of intron 8 in lipoprotein lipase in the Essential Hypertension group showed obvious differences compared with the control group. Serum triglyceride levels were higher in the patients with H+H+ genotype than in those in non H+H+ genotype of intron 8 in lipoprotein lipase by HindIII digestion. The systolic blood pressure showed a decreasing tendency among the H+H+ genotype, the H+H- genotype and the H-H- genotype individuals. CONCLUSION: The results suggest that lipoprotein lipase may be an important genetic factor associated with the Chinese Han race Essential Hypertension patients. The polymorphisms of intron 8 in lipoprotein lipase influence the blood-lipid metabolism, induce blood vessel rebuilding and play an important role in the invasion and development of Essential Hypertension.