Hepatic Lactate Dehydrogenase Research Articles

Hepatic Lactate Dehydrogenase A: An RNA Interference Target for the Treatment of All Known Types of Primary Hyperoxaluria

IntroductionPrimary hyperoxaluria (PH) is a family of 3 rare genetic disorders of hepatic glyoxylate metabolism that lead to overproduction and increased renal excretion of oxalate resulting in progressive renal damage. LDHA inhibition of glyoxylate-to-oxalate conversion by RNA interference (RNAi) has emerged as a potential therapeutic option for all types of PH. LDHA is mainly expressed in the liver and muscles.MethodsNonclinical data in mice and nonhuman primates show that LDHA inhibition by RNAi reduces urinary oxalate excretion and that its effects are liver-specific without an impact on off-target tissues, such as the muscles. To confirm the lack of unintended effects in humans, we analyzed data from the phase I randomized controlled trial of single-dose nedosiran, an RNAi therapy targeting hepatic LDHA. We conducted a review of the literature on LDHA deficiency in humans, which we used as a baseline to assess the effect of hepatic LDHA inhibition.ResultsBased on a literature review of human LDHA deficiency, we defined the phenotype as mainly muscle-related with no liver manifestations. Healthy volunteers treated with nedosiran experienced no drug-related musculoskeletal adverse events. There were no significant alterations in plasma lactate, pyruvate, or creatine kinase levels in the nedosiran group compared with the placebo group, signaling the uninterrupted interconversion of lactate and pyruvate and normal muscle function.ConclusionPhase I clinical data on nedosiran and published nonclinical data together provide substantial evidence that LDHA inhibition is a safe therapeutic mechanism for the treatment of all known types of PH.

Influence of inclusion of pigeon pea ( Cajanus cajan ) leafmeal on growth, physio‐metabolic and immune parameters, and expression of IGF‐1, IGF‐1R and IGFBP‐1 genes in Labeo rohita (Hamilton, 1822) fingerlings

A feeding trial was conducted with inclusion levels of Cajanus cajan leafmeal (CCLM) in the diet of Labeo rohita to study the growth, haematological indices, digestive enzyme, physio-metabolic changes and molecular expression of insulin-like growth factor-1 (IGF-1), insulin-like growth factor-binding protein-1 (IGFBP-1), insulin-like growth factor-1 receptor (IGF-1R) genes. Four practical diets with CCLM, control, T20 (20%), T30 (30%) and T40 (40%) were prepared. Weight gain%, SGR, FER and PER were significantly (p < 0.05) higher when 30% de-oiled rice bran (DORB) was replaced by CCLM whereas the treatment group 40% registered with lower FCR value. The protease and amylase activities were higher in the T30 group. T20 showed significantly higher (p < 0.05) hepatic and muscular lactate dehydrogenase and serum glucose was also higher, whereas, WBC content was found significantly (p < 0.05) higher in control. The hepatic IGF-1 gene expression was significantly higher (p < 0.05) in T40 followed by the T30 group but the weight gain was not significantly (p > 0.05) higher in T30 from the T40 group. Results reveal that the response of IGF-1, IGF-1R and IGFBP-1 genes was complementary to the biological growth parameters and hence were used as an indicator to evaluating growth. The study also demonstrates that CCLM can replace 100% DORB in the diet of L. rohita without any antinutritional or adverse growth effects.

Knockdown of lactate dehydrogenase by adeno-associated virus-delivered CRISPR/Cas9 system alleviates primary hyperoxaluria type 1.

BackgroundPrimary hyperoxaluria type 1 (PH1) is a rare genetic disorder caused by endogenous overproduction of hepatic oxalate, leading to hyperoxaluria, recurrent calcium oxalate kidney stones, and end‐stage renal disease. Lactate dehydrogenase (LDH) is an ideal target for diminishing oxalate production as it is responsible for glyoxylate to oxalate conversion in the liver, the last step of oxalate metabolism. Here, we investigated the therapeutic efficacy and potential side effects of clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology to ameliorate PH1 via specifically disrupting the hepatic LDH.MethodsPheochromocytoma (PC12) cells were used to assess the efficacy of cleavage of single‐guide RNAs in vitro. PH1 neonatal rats were injected with a single administration of adeno‐associated virus to deliver the CRISPR/Cas9 system that targeted LDH. Three weeks after injection, a liver biopsy was performed to detect LDH expression, liver injury, and liver metabolomics. Urinary oxalate was regularly monitored, and renal calcium oxalate deposition was evaluated after 4 weeks of 0.5% ethylene glycol challenge. After 6 months of treatment, animals were euthanized, and ex‐liver organs were harvested for toxicity analysis.ResultsThe Ldha gene was specifically knocked out in 20% of the liver cells of PH1 rats in the treatment group, leading to a 50% lower LDH expression than that in the control group. Compared to the control groups, urinary oxalate levels were significantly decreased, and renal calcium oxalate precipitation was largely mitigated in the treatment group throughout the entire 6‐month study period. While no CRISPR/Cas9‐associated off‐target edits or hepatotoxicity were detected, we observed mild metabolic changes in the liver tricarboxylic acid (TCA) and glycolysis pathways.ConclusionsCRISPR/Cas9‐mediated LDH disruption may represent an applicable new strategy for alleviating PH1 for its long‐lasting effect and low editorial efficiency requirements.

Optimum dietary crude protein for culture of genetically improved farmed tilapia (GIFT), Oreochromis niloticus (Linnaeus, 1758) juveniles in low inland saline water: Effects on growth, metabolism and gene expression

A 60-day feeding trial was conducted to determine the effects of dietary crude protein (CP) on growth, metabolism and growth-related gene expression in genetically improved farmed tilapia (GIFT), Oreochromis niloticus juveniles reared in low inland saline water (ISW) of 5 g/l salinity. Three hundred and fifteen fish (initial weight 2.68 ± 0.01 g) were distributed (15 fish/tank in triplicates) in seven experimental groups (20–50% CP with 5% increment) following completely randomized design (CRD) and fed with seven isolipidic (6%), isoenergetic (16.74 MJ digestible energy/kg) and hetero-nitrogenous (20–50 % CP) purified diets, respectively. Results showed inverse relation between percent weight gain (WG%) and feed conversion ratio which were significantly (p < 0.05) varied in overall, linearly and quadratically due to varying dietary CP. Overall and linear trend of protein efficiency ratio and overall, linear and quadratic trend of apparent net protein utilisation were significantly (p < 0.05) decreased with increasing dietary CP. Overall, linear and quadratic trend of whole body CP along with overall and quadratic trend of whole body lipid contents were significantly (p < 0.05) increased and decreased, respectively with increasing dietary CP up to 35 % and then decreased further. Whereas, overall, linear and quadratic trend of whole body ash content was increased significantly (p < 0.05) with increasing dietary CP. Overall and quadratic trend of protease activity in 30–45 % CP fed groups was significantly higher (p < 0.05) than 20 and 50 % CP fed groups; but overall and linear trend of amylase activity in 20−25 % CP fed groups was significantly higher (p < 0.05) than 35–50 % fed groups. Overall, linear and quadratic trend of hepatic glutamate pyruvate transaminase activity in 40 % CP fed group was significantly lower (p < 0.05) than that of 20−25 and 45–50 % CP fed groups and similar to 30–35 % CP fed groups. However, these trends of hepatic lactate dehydrogenase activity of 40–45 % CP fed groups was significantly lower (p < 0.05) than 20–30 % fed groups and similar to 35 and 50 % CP fed groups. Whereas, overall, linear and quadratic trend of hepatic malate dehydrogenase in 35 % fed group was significantly lower (p < 0.05) than 20–30 % CP fed groups and similar to other groups. The hepatic insulin like growth factor-1 (IGF-1) and IGF-1 receptor expression showed high correlation (r=0.92 and 0.90, respectively) with WG%. The optimum dietary protein requirement of GIFT juveniles at 5 g/l salinity in ISW was found to be 34.53–38.10% based on both broken-line linear and second-order polynomial regression with respect to WG% and hepatic IGF-1 expression.

Prophylactic endovascular balloon occlusion of the aorta in cases of placenta accreta spectrum during caesarean section: points from the anaesthesiologist\u2019s perspective

BackgroundThe placenta accreta spectrum (PAS) is a severe complication of pregnancy and is associated with massive haemorrhage, hysterectomy, and even perinatal maternal-foetal death. Prophylactic abdominal aortic balloon occlusion (PAABO) is a novel and efficient therapy for these patients. The aim of this study was to investigate the benefits, potential risks, and characteristics of anaesthesia management.MethodsA total of 48 parturients with PAS were enrolled and divided into two groups. Group A (n = 25) received PAABO, and Group B (n = 23) underwent a normal operative procedure. The characteristics of the general parameters, anaesthesia, and operative procedure were noted. Data on vital signs including systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) during the operation were recorded. Before and after the procedure, hepatic and renal function and lactate dehydrogenase (LDH) were also measured.ResultsThe characteristics of the groups were comparable. PAABO significantly reduced estimated blood loss, which was ≥ 1000 ml. Drastic fluctuations in SBP, DBP and HR were observed during inflation and deflation in Group B. After the operation, increased LDH and glutamic oxaloacetic transaminase (GOT) were observed in both groups, and increased glutamic-pyruvic transaminase (GTP) was observed in Group B.ConclusionsPAABO reduced perioperative blood loss and the risk of hysterectomy among parturients with PAS. Sophisticated anaesthetic management should be implemented to prevent or reduce perioperative complications and address internal disorders that are caused by massive blood loss.

Stiripentol identifies a therapeutic target to reduce oxaluria.

Oxalate is a metabolic end-product promoting the formation of calcium oxalate crystals in urine. Massive urine oxalate excretion occurs in genetic diseases, mainly primary hyperoxaluria type I and II, threatening renal function. Ethylene glycol poisoning may induce the precipitation of calcium oxalate crystals in renal tubules, leading to acute renal failure. In both cases, oxalate results from glyoxylate transformation to oxalate in the liver, by lactate dehydrogenase (LDH) enzymes, especially the LDH-5 isoenzyme. The purpose of the review is to highlight LDH as a potential therapeutic target according to recent publications. Genetic therapy targeting LDH metabolism decreases urine oxalate excretion in rodents. Stiripentol is an antiepileptic drug that has been shown recently to inhibit neuronal LDH-5 isoenzyme. Stiripentol was hypothesized to reduce hepatic oxalate production and urine oxalate excretion. In vitro, stiripentol decreases oxalate synthesis by hepatocytes. In vivo, stiripentol oral administration decreases urine oxalate excretion in rats and protects renal function and renal tissue against ethylene glycol intoxication and chronic calcium oxalate crystalline nephropathy. The use of stiripentol in-vitro and in-vivo highlights that targeting hepatic LDH by pharmacological or genetic tools may decrease oxalate synthesis, deserving clinical studies.

Stiripentol fails to lower plasma oxalate in a dialysis-dependent PH1 patient

BackgroundPrimary hyperoxaluria type 1 (PH1) is a multisystemic metabolic disorder caused by an excessive production of oxalate by the liver. The majority of patients presenting in early infancy have end-stage renal disease (ESRD). While awaiting the results of sRNAi trials, the current standard treatment is combined liver-kidney transplantation. Recently, Stiripentol has been reported as a promising drug in the treatment of primary hyperoxaluria by reducing urinary oxalate (UOx). Stiripentol is an anti-convulsive drug used in the treatment of children suffering from Dravet syndrome. It causes blockage of the last step in oxalate production by inhibition of hepatic lactate dehydrogenase 5 (LDH5).CaseWe administered Stiripentol as compassionate use in an anuric infant with dialysis-dependent PH1 over a period of 4 months. Although achieving plasma concentrations of Stiripentol that were recently reported to lower UOx excretion, we did not observe significant reduction to plasma oxalate concentrations (POx).ConclusionWe conclude that Stiripentol may not be useful to reduce POx in PH patients with advanced chronic kidney disease (CKD), but larger studies are needed to confirm this finding.

Inhalation of molecular hydrogen prevents ischemia-reperfusion liver damage during major liver resection.

Liver resection is a surgical procedure associated with a high risk of hepatic failure that can be fatal. One of the key mechanisms involves ischemia-reperfusion damage. Building on the well-known positive effects of hydrogen at mitigating this damage, the goal of this work was to demonstrate the antioxidant, anti-inflammatory, and anti-apoptotic effects of inhaled hydrogen in domestic pigs during major liver resection. The study used a total of 12 domestic pigs, 6 animals underwent resection with inhaled hydrogen during general anesthesia, and 6 animals underwent the same procedure using conventional, unsupplemented, general anesthesia. Intraoperative preparation of the left branch of the hepatic portal vein and the left hepatic artery was performed, and a tourniquet was applied. Warm ischemia was induced for 120 minutes and then followed by liver reperfusion for another 120 minutes. Samples from the ischemic and non-ischemic halves of the liver were then removed for histological and biochemical examinations. An evaluation of histological changes was based on a numerical expression of damage based on the Suzuki score. Liver samples in the group with inhaled hydrogen showed a statistically significant reduction in histological changes compared to the control group. Biochemical test scores showed no statistically significant difference in hepatic transaminases, alkaline phosphatase (ALP), lactate dehydrogenase (LD), and lactate. However, a surprising result was a statistically significant difference in gamma-glutamyl-transferase (GMT). Marker levels of oxidative damage varied noticeably in plasma samples. In this experimental study, we showed that inhaled hydrogen during major liver resection unquestionably reduced the level of oxidative stress associated with ischemia-reperfusion damage. We confirmed this phenomenon both histologically and by direct measurement of oxidative stress in the organism.

Benefits of thymol supplementation on performance, the hepatic antioxidant system, and energetic metabolism in grass carp.

Thymol is an herbal food additive used to improve animal performance. Thymol acts via its potential to enhance productive and reproductive performance, and by improving bioavailability of nutrients in fish. Nevertheless, the exact mechanisms associated with these phenomena remain poorly understood, although recent evidence has suggested the involvement of the phosphotransfer network and antioxidant status. Therefore, the aim of this study was to determine whether the improvement of the antioxidant/oxidant status and the phosphoryl transfer network may be involved in enhanced growth performance in grass carp (Ctenopharyngodon idella) fed with various levels of thymol (100, 200, and 300 mg/kg feed). Thymol-supplementation (100 mg/kg feed) produced higher body weight and weight gain for 60-day post-feeding compared to the control group. Specific growth rate was higher; while feed conversion ratio was lower in fish that consumed 100 mg of thymol/kg compared to other groups. Hepatic lactate dehydrogenase activity and lipid peroxidation levels were lower in the thymol-supplemented group (100 mg/kg feed) than in the control group, while reactive oxygen species were lower in all supplemented groups than in the control group. Hepatic superoxide dismutase (300 mg/kg feed) and glutathione peroxidase (100, 200, and 300 mg/kg feed) activities, as well as antioxidant capacity against peroxyl radicals (100 mg/kg feed) were higher in these groups than in the control group. Based on these data, we conclude that 100 mg thymol/kg dietary supplementation increased growth performance of fingerling grass carp. Finally, hepatic adenylate kinase activity was lower in the thymol supplemented group (100 mg/kg feed) than in the control group. Thymol supplementation (100 mg/kg feed) improved hepatic energy metabolism, while practically all tested concentrations of thymol enhanced hepatic antioxidant status, all of which may be pathways involved in increased growth performance in fingerling grass carp.

Fructose-associated hepatotoxicity indexed by the lactate dehydrogenase isoenzyme LDH-5

Modern diets have become increasingly rich in fructose, for example through the addition of high-fructose corn syrup to many foods and drinks. It has been suggested that this might lead to hepatotoxicity, including the development of non-alcoholic fatty liver disease. After entering hepatocytes via insulin-independent glucose transporter 2 transmembrane carrier proteins, fructose is phosphorylated to fructose-1-phosphate in a reaction catalysed by fructokinase (ketohexokinase). In turn, fructose-1-phosphate is hydrolysed by aldolase B to glyceraldehydes. Glyceraldehydes may enter gluconeogenesis via fructose-1,6-bisphosphate and fructose-6-phosphate; glyceraldehydes may also enter glycogenolysis via pyruvate. The last pathway involves conversion of pyruvate to acetyl-CoA. Alternatively, pyruvate may be converted, via the action of the hepatic lactate dehydrogenase isoenzyme LDH-5, into lactate. In liver damage, the LDH-5 isoenzyme becomes elevated, predominantly in serum/plasma. We therefore hypothesised that if dietary fructose is associated with hepatotoxicity, there should be a positive correlation between erythrocyte fructose-6-phosphate and plasma LDH-5. This hypothesis was tested by assaying venous blood samples taken from 39 patients at rest, three hours after eating. Quantitative Fourier transform infrared spectrometry following gel electrophoresis was used to assay erythrocyte fructose-6-phosphate levels. Similarly, plasma LDH-5 concentrations were spectrophotometrically analysed, using the pyruvate-lactate reaction, following electrophoretic separation of the LDH isoenzymes. A significant positive correlation was found between the two variables (r = 0.44, p = 0.0047). This result, which supports our hypothesis, is evidence in favour of the possibility that dietary fructose is associated with hepatotoxicity. In addition to being a marker of hepatic damage, LDH-5 may play a more direct epigenetic role in causing liver damage; acute hepatic injury is associated with nuclear translocation of LDH, causing the production of lactate from pyruvate in the nucleus; in turn, the lactate inhibits histone deacetylase and is associated with upregulation of genes associated with the damage response, leading to cell death.

Vegetable choline improves growth performance, energetic metabolism, and antioxidant capacity of fingerling Nile tilapia (Oreochromis niloticus)

Fish represents an important source of proteins and essential micronutrients for human health, and Nile tilapia (Oreochromis niloticus) is one of the most widespread aquaculture species grown worldwide to meet the growing demand for fish. In this sense, the use of supplemented diets it is important and an interesting approach to improve the growth performance, as the use of vegetable choline (VC). A total of 160 fingerlings Nile tilapia (7.10 ± 0.45 g; 6.13 ± 0.59 cm) were randomly separated into four groups in quadruplicate with 10 fish per aquarium (60 L) as follows: the group T0 (basal diet without VC supplementation), T400 (basal diet supplemented with 400 mg VC/kg of feed), (basal diet supplemented with 800 mg VC/kg of feed), and T1200 (basal diet supplemented with 1200 mg VC/kg of feed), being fed with rate of 6% of total biomass for 60 consecutive days in two equal portions and offered to fish twice a day at 9:00 am and 17:00 h. Thus, the aim of this study was to evaluate whether phosphoryl transfer network, as well as the improvement of antioxidant/oxidant status, can be considered pathways involved in the improvement of growth performance in Nile tilapia (7.10 ± 0.45 g) fed 0.0, 400, 800, and 1200 mg VC/kg of feed for 60 days. VC-supplemented diets were able to increase fish growth and feed intake after 60 days post-feeding compared to the control group. Also, fish from groups supplemented with 800 and 1200 mg VC/kg of feed presented an increase on hepatic pyruvate kinase activity compared to the control group. On the other hand, fish supplemented with 1200 mg VC/kg of feed presented an increase on hepatic glucose levels, while the hepatic lactate levels decreased compared to the control group. Additionally, VC supplementation improves the zootechnical performance. Finally, fish from groups supplemented with 800 and 1200 mg VC/kg of feed presented lower hepatic lactate dehydrogenase and lipid peroxidation levels, while the antioxidant capacity against peroxyl radicals levels were higher compared to the control group. Based on these evidences, VC supplementation can be an interesting alternative to increase growth performance of Nile tilapia fingerlings especially at levels of 800 and 1200 mg VC/kg of feed, which were able to improve the hepatic energy metabolism and antioxidant/oxidant status and subsequently increased the fish growth performance.

Sodium acetate improves disrupted glucoregulation and hepatic triglyceride content in insulin-resistant female rats: involvement of adenosine deaminase and dipeptidyl peptidase-4 activities.

Combined oral contraceptive (COC) treatment has been shown to be associated with glucose deregulation and increased triglyceride levels, but the mechanisms are elusive. Soluble dipeptidyl peptidase-4 (sDPP-4) and adenosine deaminase (ADA) are involved in the initiation and/or progression of cardiometabolic disorders. We therefore, hypothesized that increased DPP-4 and ADA activities are involved in glucose deregulation and hepatic triglyceride accumulation induced by COC treatment. This study also investigated whether short-chain fatty acid, acetate, would protect against COC-induced dysmetabolic effects. Female Wistar rats received (p.o.) vehicle and COC (1.0μg ethinylestradiol plus 5.0μg levonorgestrel) with or without sodium acetate (ACE; 200mg) for 8weeks. Treatment with COC led to increased plasma triglyceride-glucose index, 1-h postload glucose response, insulin, free fatty acid, insulin resistance, and impaired glucose tolerance. COC treatment also resulted in increased plasma and hepatic triglycerides (TG), TG/HDL-cholesterol ratio, malondialdehyde, uric acid, lactate dehydrogenase, DPP-4, ADA, and xanthine oxidase (XO) activities. On the other hand, COC led to reduction in nitric oxide level. However, ACE significantly ameliorated the alterations induced by COC treatment, but XO activity remains elevated during COC treatment. This result also demonstrates that increased DPP-4 and ADA activities are at least in part involved in glucose deregulation and hepatic TG accumulation induced by COC treatment. Therefore, sodium acetate would impact positively on cardiometabolic disorders, at least in part, by inhibition of DPP-4 and ADA activities.

A4800 Dipeptidyl peptidase-4 inhibition prevents increased hepatic triglyceride content in insulin-resistant female rats

Objectives: Dipeptidyl peptidase-4 (DPP-4) inhibition has been show to exert beneficial effects against insulin resistance (IR) and fatty liver disease. Combined oral contraceptive (COC) treatment has been shown to be associated with glucose deregulation and increased hepatic triglyceride (TG) levels, but the mechanisms are elusive. We therefore, hypothesized that DPP-4 inhibition (DPP-4i) will ameliorate COC-induced glucose dysregulation and hepatic TG accumulation through adenosine deaminase (ADA) /xanthine oxidase (XO) /uric acid-dependent pathway. Methods: Female Wistar rats received (po) vehicle and COC (1.0 μg ethinylestradiol plus 5.0 μg levonorgestrel; po) with or without DPP-4 inhibitor (sitagliptin; 100 mg/kg; po) for 8 weeks (n = 6/group). Glucose dysmetabolism was accessed by elevated fasting blood glucose, impaired oral glucose tolerance test and homeostatic model assessment of insulin resistance. Results: Treatment with COC led to increased plasma fasting glucose, triglyceride-glucose index, 1-h postload glucose response, insulin, free fatty acid, IR and impaired glucose tolerance. COC treatment also resulted in increased plasma and hepatic triglycerides (TG), TG/HDL-cholesterol ratio, malondialdehyde, uric acid, lactate dehydrogenase, DPP-4, ADA and XO activities. On the other hand, COC led to reduction in nitric oxide level. However, DPP-4i significantly ameliorated these alterations induced by COC treatment except plasma and hepatic XO activity. Conclusion: This demonstrates that increased uric acid, DPP-4 and ADA activities are involved in glucose dysregulation and hepatic TG accumulation induced by COC treatment. Therefore, DPP-4i would impact positively on cardiometabolic disorders, at least in part, through ADA and uric acid suppression.

Malaysian propolis, metformin and their combination, exert hepatoprotective effect in streptozotocin-induced diabetic rats

AimsHepatic oxidative stress and weak antioxidant defence system resulting in hepatic lesion, has been reported in diabetic rats. The present study investigated the possible hepatoprotective effects of Malaysian propolis (MP) in diabetic rats, on the background that MP has been reported to have anti-hyperglycemic, antioxidant and anti-inflammatory effects. Materials and methodsSprague-Dawley rats were randomly divided into 5 groups, namely: normal control (NC), diabetic control (DC), diabetic on 300 mg/kg b.w. MP, diabetic on 300 mg/kg b.w. metformin, and diabetic on MP and metformin combined therapy. Treatment was done orally for 4 weeks, and NC and DC groups received distilled water as vehicle. Key findingsResults showed increased fasting blood glucose and serum markers of hepatic lesion (aspartate aminotransferase, alkaline phosphatase, alanine aminotransferase and gamma-glutamyl transferase), increased hepatic lactate dehydrogenase activity, decreased hepatic superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase and glutathione reductase activities, increased immunoexpressions of nuclear factor kappa B, tumor necrosis factor-α, interleukin(IL)-1β and caspase-3, and decreased immunoexpressions of IL-10 and proliferating cell nuclear antigen in the liver of DC group. Histopathology of the liver revealed numerous hepatocytes with pyknotic nuclei and inflammatory infiltration, while periodic acid-schiff staining decreased in the liver of DC group. Treatment with MP attenuated these negative effects and was comparable to metformin. Furthermore, these effects were better attenuated in the combined therapy-treated diabetic rats. SignificanceMalaysian propolis attenuates hepatic lesion in DM and exerts a synergistic protective effect with the anti-hyperglycemic medication, metformin.

Sodium acetate and androgen receptor blockade improve gestational androgen excess-induced deteriorated glucose homeostasis and antioxidant defenses in rats: roles of adenosine deaminase and xanthine oxidase activities

Nutritional challenges and androgen excess have been implicated in the development of gestational diabetes and poor fetal outcome, but the mechanisms are not well delineated. The effects of short chain fatty acid (SCFA) on glucose dysmetabolism and poor fetal outcome induced by gestational androgen excess is also not known. We tested the hypothesis that blockade of androgen receptor (AR) and suppression of late gestational androgen excess prevents glucose dysmetabolism and poor fetal outcome through suppression of adenosine deaminase (ADA)/xanthine oxidase (XO) pathway. Twenty-four pregnant Wistar rats were treated (sc) with olive oil, testosterone propionate (0.5 mg/kg) singly or in combination with SCFA (sodium acetate; 200 mg/kg; p.o.) or AR blocker (flutamide; 7.5 mg/kg; p.o.) between gestational days 14 and 19. The results showed that late gestational androgen excess led to glucose deregulation, poor fetal outcome, increased plasma and hepatic free fatty acid and lactate dehydrogenase, liver function marker enzymes, malondialdehyde, uric acid, ADA and XO activities. Conversely, gestational androgen excess resulted in reduced body weight gain, visceral adiposity, plasma and hepatic anti-oxidant defenses (glutathione peroxidase, reduced glutathione/glutathione disulphide ratio, glucose-6-phosphate dehydrogenase, adenosine and nitric oxide). However, all these effects were ameliorated by either sodium acetate or flutamide treatment. The study demonstrates that suppression of testosterone by SCFA or AR blockade protects against glucose deregulation and poor fetal outcome by improvement of anti-oxidant defenses and replenishment of hepatic oxidative capacity through suppression of ADA/XO pathway. Hence, utility of SCFA should be encouraged for prevention of glucose dysmetabolism and poor fetal outcome.

Specific Inhibition of Hepatic Lactate Dehydrogenase Reduces Oxalate Production in Mouse Models of Primary Hyperoxaluria.

Primary hyperoxalurias (PHs) are autosomal recessive disorders caused by the overproduction of oxalate leading to calcium oxalate precipitation in the kidney and eventually to end-stage renal disease. One promising strategy to treat PHs is to reduce the hepatic production of oxalate through substrate reduction therapy by inhibiting liver-specific glycolate oxidase (GO), which controls the conversion of glycolate to glyoxylate, the proposed main precursor to oxalate. Alternatively, diminishing the amount of hepatic lactate dehydrogenase (LDH) expression, the proposed key enzyme responsible for converting glyoxylate to oxalate, should directly prevent the accumulation of oxalate in PH patients. Using RNAi, we provide the first in vivo evidence in mammals to support LDH as the key enzyme responsible for converting glyoxylate to oxalate. In addition, we demonstrate that reduction of hepatic LDH achieves efficient oxalate reduction and prevents calcium oxalate crystal deposition in genetically engineered mouse models of PH types 1 (PH1) and 2 (PH2), as well as in chemically induced PH mouse models. Repression of hepatic LDH in mice did not cause any acute elevation of circulating liver enzymes, lactate acidosis, or exertional myopathy, suggesting further evaluation of liver-specific inhibition of LDH as a potential approach for treating PH1 and PH2 is warranted.

Hepatotoxic responses of 4-nonylphenol on African catfish (Clarias gariepinus): antixoidant and histochemical biomarkers.

4-Nonylphenol (NP) toxicity in fish attracts much attention due to its ability in targeting several organs; however, the researches regarding its potential hepatotoxicity are conflicting and still require further investigation. Therefore, the objective of this study is to focus on this issue from the histophysiological point of view using NP intoxicated African catfish (Clarias gariepinus) as a model of hepatotoxicity. Twelve adult fish (6 per group) were divided into two groups; the first was considered as a control and the second was exposed to NP dissolved in water at a dose of 0.1mg/kg BW for 3weeks. A significant reduction in the hepatic alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase levels was observed in NP-exposed fish. Concerning the oxidant/antioxidant balance, a significant depletion in superoxide dismutase, catalase, and glutathione peroxidase was found along with a significant elevation in total peroxide and malondialdhyde. The histopathological examination of the hepatic tissues revealed that NP had marked hepatotoxic effects including hepatitis, centrilobular and focal hydropic and fatty degeneration, fatty change (steatosis), hepatic coagulative necrosis, and nuclear alterations in addition to apoptosis of hepatocytes and necrosis of endothelial cells. Depletion of the glycogen and increased in pigments (lipofuscin and hemosiderin) content in the hepatocytes were also recorded. Hemosiderosis and proliferation of the connective tissue around the blood vessels and branches of bile ducts and in the portal areas were also observed. In light of these findings, it was concluded that NP has a well-defined hepatotoxic impact paving the road towards other studies to investigate other detrimental cyto-physiological influences of this aquatic pollutant.

Feeding higher level of de-oiled rice bran causes stress to Labeo rohita fingerlings

A 60-day feeding trial was conducted with different inclusion levels of de-oiled rice bran (DORB) to study the digestive enzyme activity, physio-metabolic changes and oxidative stress in Labeo rohita fingerlings. Six iso-nitrogenous (30% crude protein), iso-lipidic (6% crude lipid) and iso-energetic (380.14Kcal/100g) semi-purified diets were prepared with the graded levels of DORB viz. 0 (control), T20 (20%), T30 (30%), T40 (40%), T50 (50%) and T60 (60%). Three hundred and fifteen (315) fingerlings with an average weight of 8±0.5g were distributed randomly in seven treatments in triplicates, following a completely randomised design (CRD). The digestive enzyme, protease and amylase activities were higher in 20, 30 and 40% DORB fed groups but the Lipase activity did not vary significantly whereas, SOD and GST activity was significantly lower (p<0.05) in the same groups. The T50 and T60 groups showed significantly higher (p<0.05) hepatic LDH (Lactate dehydrogenase), GST (Glutathione-s-transferase) and SOD activity, while RBC (Red blood cell) and WBC (White blood cell) content were found significantly lower in these groups. The catalase activity did not vary significantly (p>0.05) among treatment group. Serum glucose content was higher in the T40, T50 and T60 groups, while serum total protein, albumin, NBT (Nitroblue tetrazolium) and haemoglobin levels were not significantly different among the treatments. From the study, it can be concluded that DORB causes stress to fish when fed at higher inclusion level (50 & 60%).

Germacranolide-type sesquiterpene lactones from Smallanthus sonchifolius with promising activity against Leishmania mexicana and Trypanosoma cruzi

BackgroundLeishmaniasis and Chagas disease are life-threatening illnesses caused by the protozoan parasites Leishmania spp. and Trypanosoma cruzi, respectively. They are known as “neglected diseases” due to the lack of effective drug treatments and the scarcity of research work devoted to them. Therefore, the development of novel and effective drugs is an important and urgent need. Natural products are an important source of bioactive molecules for the development of new drugs. In this study, we evaluated the activity of enhydrin, uvedalin and polymatin B, three sesquiterpene lactones (STLs) isolated from Smallanthus sonchifolius, on Leishmania mexicana (MNYC/BZ/62/M) and Trypanosoma cruzi (Dm28c). In addition, the in vivo trypanocidal activity of enhydrin and uvedalin and the effects of these STLs on parasites’ ultrastructure were evaluated.MethodsThe inhibitory effect of the three STLs on the growth of L. mexicana amastigotes and promastigotes as well as T. cruzi epimastigotes was evaluated in vitro. The changes produced by the STLs on the ultrastructure of parasites were examined by transmission electron microscopy (TEM). Enhydrin and uvedalin were also studied in a murine model of acute T. cruzi infection (RA strain). Serum activities of the hepatic enzymes alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase were used as biochemical markers of hepatotoxicity.ResultsThe three compounds exhibited leishmanicidal activity on both parasite forms with IC50 values of 0.42–0.54 μg/ml for promastigotes and 0.85–1.64 μg/ml for intracellular amastigotes. Similar results were observed on T. cruzi epimastigotes (IC50 0.35–0.60 μg/ml). The TEM evaluation showed marked ultrastructural alterations, such as an intense vacuolization and mitochondrial swelling in both L. mexicana promastigotes and T. cruzi epimastigotes exposed to the STLs. In the in vivo study, enhydrin and uvedalin displayed a significant decrease in circulating parasites (50–71%) and no signs of hepatotoxicity were detected.ConclusionsEnhydrin, uvedalin and polymatin B possess significant leishmanicidal and trypanocidal activity on different parasite stages. These results show that these compounds may provide valuable leads for the development of new drugs against these neglected parasitic diseases.

Intranasal Delivery of Microspheres Loaded with 20 (R)-ginsenoside Rg3 Enhances Anti-Fatigue Effect in Mice.

Nasal delivery of 20 (R) -ginsenoside Rg3 (Rg3) has a short-lived anti-fatigue effect owing to rapid clearance by nasal cilia. Thus, in order to extend the residence time of Rg3 in the nasal cavity, a new drug delivery system is needed. Chitosan microspheres loaded with Rg3 were prepared using a multi-step emulsification method and were characterized in vitro and in vivo. The microspheres had a spherical shape with a mean diameter of 44.9±12.6 08m. The drugloading ratio was 10.25±0.08%, and the encapsulation ratio was 30.61±1.46%. Our in vitro mucoadhesion experiment demonstrated that 70.35±1.79% of the microspheres adhered to the nasal mucosa. The in vitro release study revealed that 31.1% of the Rg3 was released from the microspheres in the first 10 min. Release slowed, with 88.64% of the Rg3 released within 6 h. The pharmacodynamics study demonstrated that the weight-bearing swimming time of mice increased significantly from 432±89 s to 486±96 s after administration of Rg3 microspheres compared with the Rg3 water solution. Blood lactic acid and serum urea nitrogen significantly decreased in the group administered microspheres compared to the water solution group (p<0.05). Hepatic glycogen and lactate dehydrogenase increased significantly in the group administered microspheres compared to the water solution group (p<0.01). 20 (R) -ginsenoside Rg3 entrapped in chitosan microspheres may have a beneficial effect against fatigue by increasing the residence time of Rg3 in the nasal cavity and enhancing absorption by the nasal mucosa.