Intervention of curcumin and its analogue J7 on oxidative stress injury in testis of type 2 diabetic rats / 中国应用生理学杂志

OBJECTIVE@#To investigate the intervention of curcumin and its analogue J7 on oxidative stress injury in testis of type 2 diabetic rats.@*METHODS@#Sixty male SD rats, 10 rats were chosen as normal control group (NC), the other 50 rats were assigned to experiment group. Experiment diabetic rats were induced by high-fat food and intraperitoneal injection of steptozotocin (STZ). After the model was established successfully, diabetic rats were divided into four groups randomly: diabetes mellitus group (DM, n=12), curcumin treatment group (CUR, n=10), high dose treatment group of J7 (J+, n=10), low dose treatment group of J7 (J-, n=10). The CUR group were intragastrically administered with curcumin 20 mg/kg daily, in addition, the J+ group and the J- group were intragastrically administered with J7 20 mg/kg and 10 mg/kg daily respectively. After 8 weeks, the fast blood glucose was detected biochemically. The activity of superoxide dismutase (SOD) and the level of malondialdehyde (MDA) were detected by hydroxylamine method and thiobarbituric acid method respectively. The protein expressions of the nuclear factor-erythroid 2-related factor 2 (tNrf2), phosphorylation of Nrf2 (pNrf2), catalase (CAT), NAD(P)H quinine oxidoreductase 1 (NQO1) were measured by Western blot. The mRNA expressions of CAT, NQO1, hemeoxygenase-1 (HO1) were measured by quantitative real-time PCR (qRT-PCR). Morphological structure of testis was observed by hematoxylin-eosin (HE) staining. The expressions of Nrf2 and CAT were also detected by immunohistochemical method.@*RESULTS@#The levels of fast blood glucose and MDA in DM group were increased significantly(P＜0.05), while the body weight, the activity of SOD, the protein expressions of pNrf2/tNrf2, CAT, NQO1 and the mRNA expressions of CAT, NQO1, HO1 were decreased (P＜0.05). Under light microscope, the DM group showed disrupted histological appearance. Immunohistochemistry showed that the protein expressions of Nrf2 around the nucleus and CAT were decreased. With the treatment of curcumin and J7, the MDA levels in the three treatment groups were decreased (P＜0.05). The activity of SOD, the protein expressions of pNrf2/tNrf2, CAT, NQO1 and the mRNA expressions of NQO1, HO1 were increased (P＜0.05). the levels of fast blood glucose were decreased in the J+ and J- group (P＜0.05), and the mRNA expression of CAT was increased in the J+ group (P＜0.05). The ratio of pNrf2/tNrf2 in the J+ group was significantly higher than that in CUR and J- group (P＜0.05). The protein level of CAT in the J+ group was also significantly higher than that in J- group (P＜0.05). There were no significant differences in other indexes among the three treatment groups. Under light microscope, the morphology was obviously improved in the three treatment groups. Immunohistochemistry showed that the protein expressions of Nrf2 around the nucleus and CAT were increased in the three treatment groups. It was suggested that high dose J7 had better antioxidant stress ability in testis of diabetic rats.@*CONCLUSION@#Curcumin and J7 could inhibit the oxidative stress damage of testicular tissue in diabetic rats, which might be related with the activation of the Nrf2-ARE signaling pathway.

Protective effect of curcumin derivative B06 on kidney of type 2 diabetic rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To observe the effect and mechanism of curcumin derivative B06 on kidney from rats with hyperlipidemia and type 2 diabetes.</p><p><b>METHODS</b>Thirty five male SD rats were randomly divided into five groups(n = 7): the normal control group, high-fat group, high-fat + B06-treatd group, diabetic group, diabetic + B06-treated group. After fed with high-fat diet for 4 weeks, the later two groups were in- jected with streptozotocin intraperitoneally to induce type 2 diabetes mellitus. B06-treated groups were given B06 by gavage at a dosage of 0.2 mg/kg . d for 8 weeks. After the treatment, the serum creatinine, blood urea nitrogen and uric acid were detected biochemically, the morphology of kidney was observed with light and transmission electron microscopy, the expression of collagen fibers was observed with Masson staining, the protein expression of collogen IV and fibronectin in kidney were determined by Immunohistochemistry.</p><p><b>RESULTS</b>It was showed that the levels of the serum creatinine and blood urea nitrogen elevated significantly in diabetic group. In high-fat and diabetic groups, increased glomerular mesangial matrix and collagen fiber and thicken glomerular basal membrane were observed under light microscopy, swelling and fusion of foot process were found under electron microscope; increased green matrix within glomeruli was observed under Masson staining. collogen IV and fibronectin protein expression were significantly enhanced in high-fat group and diabetic group. After B06's intervention, the levels of serum creatinine and blood urea nitrogen were decreased in diabetic groups, the morphological change of kidney was obviously relieved, Collogen IV and fibronectin protein expression reduced.</p><p><b>CONCLUSION</b>Curcumin derivative B06 exerts a protective effect on kidney in type 2 diabetic rats, reduced expressions of collogen IV and fibronectin, inhibition of the accumulation of extracellular matrix and glomerular mesangial proliferation, and then prevention of renal fibrosis may be the mechanism.</p>

Effects of extract of ginkgo biloba on learning and memory ability and NGF and NT-3 expression in diabetic rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the effect of extract of Ginkgo Biloba(EGB) on nerve growth factor(NGF) and Neurotrophin-3(NT-3) expression of hippocampus neurons in streptozotocin-induced type I diabetic rats.</p><p><b>METHODS</b>Thirty male SD rats were divided into three groups (n = 10): the control group, diabetic group and EGB-treated group. Strepozotocin were injected intraperitoneally in the later two groups to induce diabetes. EGB-treated group was injected intraperitoneally with EGB, and the same volume of normal saline was injected to the other groups. Concentration of blood glucose and body weight and behaviour were dynamicly monitored. At the end of the 12th week, morphological changes of the hippocampus neurons were observed under microscopy by HE stain. The expression of NGF and NT-3 were assayed by Western blot and RT-PCR respectively.</p><p><b>RESULTS</b>Compared with diabetic group, the behaviour and body weight (P < 0.05) and the concentration of blood glucose (P < 0.05) were significantly improved and the escape latency of Morris water maze test (P < 0.05) was significantly shortened, while the platform searching score was significantly increased (P < 0.01) in EGB treated group; The pathological changes of hippocampus neurons were significantly attenuate by EGB treated; The expression of NGF and NT-3 in hippocampus neurons were significantly increased which assayed by Western blotting and RT-PCR respectively (P < 0.05) in EGB treated group.</p><p><b>CONCLUSION</b>EGB may improve the learning and memory ability of diabetic rats the mechanism may be attributed to its improvement of the expression of NGF and NT-3 and reducing apoptosis in hippocampus neurons.</p>

Effects of ginkgo biloba extraction on contraction capacity of diaphragm from type 2 diabetic rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the effects of Ginkgo biloba extract (GbE) on the activities of energy metabolism enzymes and contraction capacity of diaphragm from type 2 diabetic rats.</p><p><b>METHODS</b>Forty SD male rats were randomly divided into normal control group (n=10) and model group (n=30). Type 2 diabetes models were induced by feeding with high-sucrose-high-fat diet and intraperitoneal injecting 25 mg/kg streptozotocin. 20 successful models were rearranged to two groups: diabetic group and GbE treatment group, 10 rats in each. Then the saline and 8 mg/(kg x d) of GbE were respectively intraperitoneal injected, once a day continuously for 8 weeks. Then diaphragm contractility was assessed using Peak twitch tension (Pt), Maximum tetanic tension (P0) and fatigue index (FI) in vitro diaphragm strip preparations. Cytochrome oxidase (CCO), lactate dehydrogenase (LDH) and succinate dehydrogenase (SDH) in diaphragm were detected and the varieties of diaphragm ultrastructure were observed.</p><p><b>RESULTS</b>Compared with control group, Pt, P0 and FI in diabetic group decreased significantly (P < 0.01); the activity of CCO, LDH and SDH in the tissues was more obviously reduced than those in control group (P < 0.01). The ultrastructure in diabetic group under electron microscope indicated that diaphragm mitochondrions swelled and degenerated. The above changes were inhibited by GbE.</p><p><b>CONCLUSION</b>GbE can enhance contraction capacity of diaphragm from type 2 diabetic rats by increasing the aerobic oxidation capacity, glycolytic capacity and the function of respiratory chain.</p>

Ginkgo biloba extract enhances testosterone synthesis of Leydig cells in type 2 diabetic rats / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the effects of Ginkgo biloba extract (EGB) on the testosterone synthesis in the Leydig cells of type 2 diabetic rats.</p><p><b>METHODS</b>Thirty male SD rats were equally randomised into a normal control, a type 2 diabetic and an EGB group. Morphological changes of Leydig cells were observed by light microscopy (LM) and transmission electron microscopy (TEM), concentrations of serum luteinizing hormone (LH) and testosterone (T) were determined by enzyme linked immunosorbent assay (ELISA), and the mRNA levels in the steroidogenic acute regulatory protein (StAR), cytochrome P450 side chain cleavage (P450scc), cytochrome P450 17a-hydroxylase (P450c17), 17beta-hydroxysteroid dehydrogenase 3 (17beta-HSD3) and 3beta-hydroxysteroid dehydrogenase (3beta-HSD1) from the Leydig cells were examined by RT-PCR.</p><p><b>RESULTS</b>Compared with the normal control, there was a significant decrease in the number and volume of Leydig cells, the levels of serum LH and T and the expression of mRNA in StAR, P450scc, 17beta-HSD3 and 3beta-HSD1 in the type 2 diabetes group. And the expression of the P450c17 gene showed a tendency of descending, but with no significance. Compared with the type 2 diabetes group, 12 weeks of EGB treatment caused very slight pathological changes in the Leydig cells, significantly increased the concentrations of blood LH and T, markedly elevated the levels of mRNA in StAR and P450scc and induced an ascending tendency of the expressions of P450c17, 17beta-HSD3 and 3beta-HSD1.</p><p><b>CONCLUSION</b>EGB enhances testosterone synthesis and secretion of Leydig cells by reducing the impairment of the testis in type 2 diabetic rats.</p>

The beneficial effect of Gingko biloba extract on myocardial impairment in diabetic rats / 中国应用生理学杂志

<p><b>AIM</b>To study the protective effect of Gingko biloba extract (EGb) against myocardial impairment in diabetic rats.</p><p><b>METHODS</b>Morphology of effect of EGb on myocardium in diabetic rats was observed under light microscopy (LM) and transmission electron microscopy (TEM). Activity of super oxide dismutase (SOD), nitric oxide synthase (NOS), constitutive nitric oxide synthase (cNOS), inductive nitric oxide synthase (iNOS) and content of malondialdehyde (MDA), nitric oxide (NO) were detected biochemically in myocardial homogenate.</p><p><b>RESULTS</b>It was manifestation as vascular degeneration and local lysis of myocardial fiber under LM and swelling of mitochondria, shorten of mitochondrial crest, lysis of myofibril under TEM, the activity of SOD decreased and the activity of NOS, iNOS, the content of NO, MDA increased, but the morphological changes became slight in EGb treatment group. Activity of SOD increased while activity of NOS, iNOS and content of MDA, NO decreased in EGb treatment group compared with diabetic group.</p><p><b>CONCLUSION</b>EGb can protect diabetic myocardium and anti-lipid peroxidation and decrease of NO level may be involved in it.</p>