Protective effect of total flavonoids extracted from the leaves of Murraya paniculata (L.) Jack on diabetic nephropathy in rats

Prioritization before dereplication, an effective strategy to target new metabolites in whole extracts: ghosalin from Murraya paniculata root

Re-discovery of known metabolites is a common challenge in natural product-based drug discovery, and to avoid re-discovery, dereplication has been proposed for identifying known metabolites at the early stage of isolation. A majority of methods use LCMS to profile the extract and ignore the known mass. LC-HRMS profiling may generate a long mass list of metabolites. The identification of a new metabolite is difficult within the mass list. To overcome this, it was hypothesized that identifying a 'new metabolite' in the whole metabolome is more difficult than identifying it within the class of metabolites. A prioritization strategy was proposed to focus on the elimination of unknown and uncommon metabolites first using the designed bias filters and to prioritize the known secondary metabolites. The study employed Murraya paniculata root for the identification of new metabolites. The LC-HRMS-generated mass list of 509 metabolites was subjected to various filters, which resulted in 93 metabolites. Subsequently, it was subjected to regular dereplication, resulting in 10 coumarins, among which 3 were identified as new. Further, chromatographic efforts led to the isolation of a new coumarin, named ghosalin (1). The structure of the new compound was established through 2D NMR and X-ray crystallography. Cytotoxicity studies revealed that ghosalin has significant cytotoxicity against cancer cell lines. The proposed prioritization strategy demonstrates an alternative way for the rapid annotation of a particular set of metabolites to isolate a new metabolite from the whole metabolome of a plant extract.

A comprehensive review of the botany, phytochemistry, pharmacology, and toxicology of Murrayae Folium et Cacumen

Ethnopharmacological relevance: Murrayae Folium et Cacumen (MFC) is a plant considered to be a traditional Chinese medicine with culinary value as well. The dry leaves and twigs of Murraya paniculata and M. exotica are used to treat stomach aches, rheumatism, toothaches, swelling, and insect and snake bites. They are also used to prepare spicy chicken dishes. Aim of the review: This review comprehensively summarizes the available information on the botanical characterization, phytochemistry, pharmacological activities, pharmacodynamics, pharmacokinetics, and toxicity of MFC. Methods: Relevant scientific literature up to August 2023 was included in the study. Chinese and English studies on MFC were collected from databases, including PubMed, Elsevier, Web of Science, Springer, Science Direct, Wiley, ACS, and CNKI (Chinese). Doctoral and Master's dissertations were also included. Results: In total, 720 compounds have been identified and reported in the literature, including flavonoids, coumarins, alkaloids, sterols, phenylpropenols, organic acids, spirocyclopentenones, and volatile oils. Flavonoids and coumarins are the two most important bioactive compounds responsible for these pharmacological activities. MFC has anti-inflammatory, anti-bacterial, anti-microbial, anti-diabetic, anti-tumor, anti-oxidant, anti-depressant, potential anti-Alzheimer's disease, chondroprotective, and analgesic properties. The pharmacological effects include interrupting the STAT3/NF-κB/COX-2 and EGFR signaling pathways, downregulating EpCAM expression, inhibiting NF-κB and ERK signals, inhibiting the EP/cAMP/PKA signaling pathway and miR-29a/Wnt/β-catenin signaling activity, and upregulating Foxo3a expression. Conclusion: This review demonstrates that the chemical constituents, pharmacological activities, pharmacodynamics, pharmacokinetics, and toxicity of MFC support its use in traditional Chinese botanical medicines. MFC contains a wide range of chemical compounds. Flavonoids and coumarins promote strong pharmacological activity and, are low-toxicity natural phytomedicines that are widely used in medicine, food, ornamentation, and cosmetics, making MFC a promising compound for development and use in the treatment of several medical conditions.

Potential Benefits of Antioxidant Phytochemicals in Type 2 Diabetes

The clinical relationship between diabetes and inflammation is well established. Evidence clearly indicates that disrupting oxidant-antioxidant equilibrium and elevated lipid peroxidation could be a potential mechanism for chronic kidney disease associated with type 2 diabetes mellitus (T2DM). Under diabetic conditions, hyperglycemia, especially inflammation, and increased reactive oxygen species generation are bidirectionally associated. Inflammation, oxidative stress, and tissue damage are believed to play a role in the development of diabetes. Although the exact mechanism underlying oxidative stress and its impact on diabetes progression remains uncertain, the hyperglycemia-inflammation-oxidative stress interaction clearly plays a significant role in the onset and progression of vascular disease, kidney disease, hepatic injury, and pancreas damage and, therefore, holds promise as a therapeutic target. Evidence strongly indicates that the use of multiple antidiabetic medications fails to achieve the normal range for glycated hemoglobin targets, signifying treatment-resistant diabetes. Antioxidants with polyphenols are considered useful as adjuvant therapy for their potential anti-inflammatory effect and antioxidant activity. We aimed to analyze the current major points reported in preclinical, in vivo, and clinical studies of antioxidants in the prevention or treatment of inflammation in T2DM. Then, we will share our speculative vision for future diabetes clinical trials.

Diversity in Phytochemical Composition and Medicinal Value of Murraya paniculata

Murraya paniculata is herbal medicinal plant which is traditionally being used for management of cardiovascular, intestinal and respiratory (air way) disorders. This evergreen plant of tropical regions is a member of Rutaceace family. The goal of this review is to analyze and report the biological activities and active phytochemicals reported from Murraya paniculata (M. paniculata) extracts and essential oil. The data was searched using different search engines and using specific key words including M. paniculata, herbal medicine, phytochemicals, extract, essential oil, pharmacological activities. M. paniculata has been found to have wide range of pharmacological activities, including antinociceptive, antianxiety, antioxidant, antidepressant, antibacterial, analgesic and anti-diabetic properties. A diverse range of phytochemicals, including phenols, coumarins, terpenoids, flavonoids, and alkaloids have been isolated from various portions of the plant and tested for a variety of biological activities. This review will provide more information and stimulate additional research to develop more effective and cost-efficient alternative medicine from this plant.

Impact of licochalcone A on the progression of diabetic nephropathy in type 2 diabetes mellitus of C57BL/6 mice

Diabetic nephropathy (DN) is the most common chronic microvascular complication of diabetes. Therefore, it is of great significance to effectively prevent and treat DN. Licochalcone A (LicA) is a flavonoid found in licorice; previous studies have shown that LicA can reduce blood glucose, blood lipids and improve insulin resistance. There has been no research on whether LicA can prevent and treat DN. In this study, an animal model of type 2 diabetes mellitus (T2DM) mice induced by high fat diet/streptozotocin was established, and the intervention of LicA was applied to investigate the protective effect of LicA on the kidneys of DN mice. After 4 weeks of intervention, LicA could effectively reduce blood glucose and alleviate the phenomenon of weight loss in mice. Meanwhile, the levels of MDA, SOD and GSH-Px in the kidney tissue and serum were recovered to different degrees. Besides, LicA decreased the levels of TC, TG and LDL-C in the kidney tissue and increased the level of HDL-C in the kidney tissue. The 24 h urinary protein, blood urea nitrogen (BUN) and serum creatinine (SCr) levels of mice in the treatment group of LicA were significantly lower than those in the model group. Furthermore, HE staining, PAS staining and Masson staining indicated that LicA improved the pathological damage of kidneys, and the kidney index of mice also decreased. Western blotting results indicated that LicA could significantly down-regulate the protein expression of AGEs/RAGE, TGF-β1, HIF-1α and GLUT1, and up-regulate the protein expression of Nrf2. It provides a theoretical basis for the further development and utilization of LicA.

Comparison of Murraya exotica and Murraya paniculata by fingerprint analysis coupled with chemometrics and network pharmacology methods

There are two source plants for the traditional Chinese medicine Murrayae Folium et Cacumen (MFC) in Chinese Pharmacopoeia, i.e. Murraya exotica L. and M. paniculata (L.) Jack. Herein, a chemical comparison of M. exotica and M. paniculata by high performance liquid chromatography (HPLC) fingerprint analysis coupled with chemometrics and network pharmacology was performed. The main peaks in the fingerprints were identified by liquid chromatography coupled with ion trap/time-of-flight mass spectrometry (LC-IT-TOF-MS) and authenticated by references. The chemometrics results showed that the HPLC fingerprints of these two species were clearly divided into two categories using hierarchical cluster analysis (HCA) and principal component analysis (PCA), and a total of 13 significantly differentiated markers were screened out by orthogonal partial least squares-discriminant analysis (OPLS-DA). However, the following network pharmacology analysis showed that these discriminated markers were found to act via many common targets and metabolic pathways, indicating the possibly similar pharmacological effects and mechanisms for M. exotica and M. paniculata. The above results provide valuable evidence for the equivalent use of these two plants in clinical settings. Moreover, the chromatographic fingerprint analysis coupled with chemometrics and network pharmacology supplies an efficient approach for the comparative analysis of multi-source TCMs like MFC.

Arbutin attenuates ethanol-induced acute hepatic injury by the modulation of oxidative stress and Nrf-2/HO-1 signaling pathway

Alcoholic liver disease (ALD) is a pervasive ailment due to the excessive consumption of alcohol and there is no operative drug for its treatment. The current exploration was intended to examine the hepatoprotective efficacy of arbutin against ethanol-provoked liver injury in rats via the modulation of the Nrf-2/HO-1 signaling cascade. Wistar rats were challenged with the 3 g/kg/day (40% v/v) of ethanol for 4 weeks to provoke the ALD and concomitantly supplemented with 40 mg/kg of arbutin. The liver function markers enzymes, inflammatory cytokines, and oxidative stress markers levels were scrutinized by using the respective assay kits. The mRNA expression of Nrf-2/HO-1 signaling proteins was studied by reverse-transcription polymerase chain reaction. The histological alterations of liver tissues were examined. HepG2 cells were used for the in vitro studies. The levels of oxidative stress markers and liver marker enzymes were examined by using kits. Reactive oxygen species (ROS) and apoptotic cell death was detected by using fluorescent staining. There were no major differences in the body weight and liver weight of experimental animals. Arbutin treatment appreciably reduced the liver marker enzymes, upregulated superoxide dismutase, glutathione peroxidase, total antioxidant capacity, and the hydroxyl scavenging ability, and diminished the tumor necrosis factor-α and interleukin-6 levels in the serum of ethanol provoked animals. Arbutin triggered Nrf-2/HO-1 signaling cascade liver tissues of ethanol-provoked animals. Histological findings proved the preventing effects of arbutin. Arbutin did not demonstrate toxicity to the HepG2 cells. It reduced the aspartate aminotransferase and alanine aminotransferase, ROS, apoptotic cell death, lipid peroxidation and improved the antioxidants' levels in the ethanol-challenged HepG2 cells. In conclusion, our findings unveiled the hepatoprotective efficacy of arbutin against ethanol-provoked liver injury in rats. It could be a promising agent to treat alcoholic liver disease in the future.

Hypoglycaemic and hypolipidemic activities of Alhagi camelorum in streptozotocin-induced diabetes in Wistar rats

This study investigates the alcoholic extract effect of Alhagi camelorum on blood glucose and lipid profiles in diabetic rats made by streptozotocin (STZ). Male rats were divided into four groups. The control group received a normal diet. The diabetic group was induced by STZ and two diabetic experimental groups received alcoholic extracts of A. camelorum at a dose of 200 and 300 mg/kg by means of gavage, respectively. Blood samples were collected on 21st from all the groups. Findings show that there is a significant increase in the level of fasting blood sugar and lipid profiles in diabetic group when the results compared to the control group (p < .05). The same factors showed a drop in groups receiving extract. The levels of insulin and high-density lipoprotein (HDL) were increased in groups that received alcoholic extract. Results indicate that alcoholic extract of A. camelorum decreases the rate of hyperglycaemia and hyperlipidaemia associated with diabetes.

Using polyphenols as a relevant therapy to diabetes and its complications, a review

Diabetes is currently a worldwide health concern. Hyperglycemia, hypertension, obesity, and oxidative stress are the major risk factors that inevitably lead to all the complications from diabetes. These complications severely impact the quality of life of patients, and they can be managed, reduced, or even reverted by several polyphenols, plant extracts and foods rich in these compounds. The goal of this review is to approach diabetes not as a single condition but rather an interconnected combination of risk factors and complications. This work shows that polyphenols have multi target action and effects and they have been systematically proven to be relevant in the reduction of each risk factor and improvement of associated complication.

Chemical profiling, in vitro antioxidant, membrane stabilizing and antimicrobial properties of wild growing Murraya paniculata from Amarkantak (M.P.)

The excessive usage of antibiotics in humans and veterinary medicine has lead to the emergence of antibiotic resistance and now requires the use of novel antibiotics. There has been increased interest towards plants as source of drugs because of their pharmacological potency and long traditional usage. The aim of the current study was to evaluate bioactive components, antioxidant, and anti-inflammatory activities of the leaf extracts of Murraya paniculata, a plant traditionally used in Indian medicinal system. Evaluations were made for phytochemical analysis, antioxidant, membrane stabilizing, and antimicrobial activities. The methanol extract displayed the highest flavonoid and phenolic content, the acetone extract demonstrated considerable ABTS inhibitory activity (IC50value:555.18 ± 1.68 µg/mL) and the hexane extract exhibited highest H2O2 radical scavenging activity (IC50value: 509.84 ± 3.03 µg/mL). The aqueous extract displayed 19.4 ± 0.66% RBC hemolysis and 80.5 ± 0.66% protection caused by hypotonic solution at high concentration of the extract. The fractions of hexane extract revealed a higher zone of inhibition than crude extract. The major components found in the fractions were cyclohexane (40.11%) and 3-(6-Methoxy-3-methyl-2-benzofuranyl) Cyclohexanone (13.68%) as analyzed by GC-MS/MS technique. The current results validate the traditional use of the M. paniculata and warrant its potential in drug development programs in further investigations.

Leaf Extracts of Anchomanes difformis Ameliorated Kidney and Pancreatic Damage in Type 2 Diabetes

Kidney disease in diabetes is one of the common microvascular complications of diabetes mellitus implicated in end-stage renal failure. This study explored the ability of Anchomanes difformis to ameliorate kidney and pancreatic damage in type 2 diabetes mellitus using male Wistar rats. Two weeks of fructose (10%) administration followed by streptozotocin (40 mg/kg) were used to induce type 2 diabetes. Leaf extract (aqueous) of Anchomanes difformis (200 mg and 400 mg/kgBW) was administered orally for six weeks. Body weights were monitored, urea and creatinine were measured. Interleukins (IL)-1β, IL-6, IL-10, IL-18, and TNFα were measured in the kidney lysate. CAT, SOD, ORAC, FRAP, and MDA levels were also evaluated in the kidney. Transcription factors (Nrf2 and NF-ĸB/p65) and apoptotic markers (Bcl2 and caspase 3) were investigated in the kidney. Histological sections of the pancreas and kidney tissues were examined for any visible pathology. Supplementation with Anchomanesdifformis enhanced antioxidant status, modulated inflammatory response, and reduced apoptosis in the kidney. It also restored the kidney and pancreatic histoarchitecture of the treated diabetic rats. The pathophysiology associated with diabetic nephropathy and pancreatic damage showcase the importance of exploring the use of antidiabetic, nephroprotective agents such as Anchomanes difformis to kidney damage in type 2 diabetes.

Curcumin and Baicalin ameliorate ethanol-induced liver oxidative damage via the Nrf2/HO-1 pathway

One of the key mechanisms of alcoholic liver disease is oxidative stress. Both Curcumin and Baicalin exert antioxidant effects, but the mechanism of their combined effects of ethanol-induced liver injury is still unclear. This study was conducted to evaluate the dual antioxidant activity of Curcumin combined with Baicalin against ethanol-induced liver injury in rats. Rats were divided into five groups, a control, ethanol, ethanol + Curcumin (50 mg/kg), ethanol + Baicalin (50 mg/kg), and ethanol + Curcumin +Baicalin group with ten rats per group. The effects of ethanol on liver enzymes, oxidative stress indicators and the levels of Nrf2/HO-1 pathway related proteins and mRNA were observed along with liver histopathology in rats. Our results found that the serum ALT and AKP levels were increased in ethanol-treated rats, which also showed a rising trend of 8-OHdG and LPO levels while hydroxyl radical scavenging ability, T-AOC, and the activities of SOD and GSH-Px were decreased in liver. The mRNA levels of Nrf2 and HO-1, the ratio of p-Nrf2/Nrf2, the protein level of HO-1 were decreased while NQO1 mRNA level, Nrf2, p-Nrf2, and NQO1 protein levels were increased in ethanol-treated rats. Combination treatment of Curcumin and Baicalin significantly reversed the ethanol-induced liver oxidative damage and further activate the Nrf2/HO-1 pathway, which was more effective than each drug alone. In conclusion, evidence has shown for the first time in this study that Curcumin combined with Baicalin ameliorated ethanol-induced liver oxidative damage in rats and revealed liver-protection. PRACTICAL APPLICATIONS: Many drugs for treating alcoholic liver disease are available commercially, but some adverse effects they have may cause secondary damage to the liver. At present, the combined treatment of different natural phytochemicals has attracted special attention in modern medicine. Curcumin, a kind of phytochemicals, is extracted from turmeric rhizome. Baicalin is one of the major active components of Scutellaria Baicalensis. The current research is to explore the antioxidant effect of Curcumin and Baicalin in ethanol-induced liver injury in rats. Our research proves that Curcumin combined with Baicalin on ethanol-induced liver oxidative damage is superior to single drug treatment. Therefore, the combination of Curcumin and Baicalin may provide a more prospective natural remedy to combat ethanol-induced liver injury.

Ampelopsin inhibits high glucose-induced extracellular matrix accumulation and oxidative stress in mesangial cells through activating the Nrf2/HO-1 pathway

Oxidative stress plays an important role in diabetic nephropathy (DN), which is a diabetic complication. Ampelopsin (AMP) is a natural flavonoid that has been found to possess antidiabetic and antioxidative activities. However, the effect of AMP on DN remains unclear. In this study, we aimed to evaluate the protective effect of AMP on glomerular mesangial cells (MCs) exposed to high glucose (HG). We found that AMP improved HG-caused cell viability reduction in MCs. AMP significantly suppressed the intracellular ROS production and expression levels of ROS producing enzymes NADPH oxidase 2 (NOX2) and NOX4. Increased of NOX activity in HG-stimulated MCs was suppressed by AMP. Pretreatment with AMP inhibited extracellular matrix (ECM) accumulation in HG-stimulated MCs with decreased expression levels of fibronectin (FN) and collagen type IV (Col IV). Furthermore, AMP elevated the expression levels of nuclear Nrf2 and heme oxygenase-1 (HO-1), as well as increased the mRNA levels of Nrf2-driven genes NAD(P)H dehydrogenase quinone-1 (NQO-1) and HO-1 in HG-treated MCs. Knockdown of Nrf2 reversed the protective effects of AMP against HG-induced oxidative stress and EMC accumulation in MCs. In conclusion, these findings indicated that AMP protected MCs from HG-induced oxidative damage and ECM accumulation, which might be mediated by Nrf2/HO-1 pathway.

Effects of total flavonoids from Oxytropis falcata Bunge on the SOCS/JAK/STAT inflammatory signaling pathway in the kidneys of diabetic nephropathy model mice

To investigate the effects of total flavonoids from Oxytropis falcata Bunge on the inflammatory signaling pathway suppressor of cytokine signaling (SOCS)/Janus kinase (JAK)/signal transducer and activator of transcription (STAT) in diabetic nephropathy KK-Ay mice. KK-Ay mice were used to establish a diabetic nephropathy model. The general condition of the mice treated with different concentrations of total flavonoids from O. falcata was monitored, respectively. Body weight, blood glucose, 24-h urinary albumin (UAlb), serum creatinine (Cre), blood urea nitrogen (BUN), and uric acid (UA) levels were measured at different time points. Hematoxylin and eosin staining quantitative reverse transcription-polymerase chain reaction and western blotting were used to detect changes in renal tissues and glomerular mesangial cells. Four weeks after model establishment, body weight, blood glucose, and 24 h UAlb significantly increased in KK-Ay mice compared with that in control C57BL/6j mice ( P < 0.05). Compared with non-treated model mice, mice treated with total flavonoids from O. falcata for 4 weeks had significantly decreased serum Cre, BUN, and UA; monocyte chemoattractant protein-1(MCP-1), nuclear factor(NF)-κB, interleukin(IL)-6, and transforming growth factor(TGF)-β1, JAK 1, STAT 3 and STAT 4 mRNA levels; and p-JAK2 and p-STAT1 protein levels and significantly increased SOCS-1 and SOCS-3 protein levels in the kidneys. The treatment effects were dose-dependent and same to in vitro. Our results reflected that total flavonoids from O. falcata relieved renal tissue inflammation in diabetic mice by reducing blood glucose levels and inhibiting JAK/STAT signaling, thereby protecting against the development of diabetic nephropathy.

Effects of β-caryophyllene and Murraya paniculata essential oil in the murine hepatoma cells and in the bacteria and fungi 24-h time-kill curve studies

CONTEXT

Orange Jessamine [Murraya paniculata L. (Rutaceae)] has been used worldwide in folk medicine as an anti-inflammatory, antibiotic and analgesic.

OBJECTIVE

The objective of this study is to investigate the in vitro antioxidant, cytotoxic, antibacterial and antifungal activity and the time-kill curve studies of orange jessamine essential oil and β-caryophyllene, as well as the chemical composition of the essential oil.

MATERIAL AND METHODS

The cytotoxic activity of M. paniculata and β-caryophyllene (7.8-500 μg/mL) was evaluated using the MTT assay on normal fibroblasts and hepatoma cells. The minimal inhibitory concentration and time-kill curves (24 h) were evaluated against those of Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, Enterococcus faecallis, Aspergillus (niger, fumigates and parasiticum) and F. solani by the broth microdilution method. The antioxidant activity was measured by the DPPH and ABTS assays. Chemical composition was evaluated by GC/MS analyses.

RESULTS

GC/MS analyses identified 13 compounds, with β-caryophyllene as the major compound. The oil exhibited moderate antibacterial activity (MIC <1.0 mg/mL) and strong antifungal activity. Time-kill curve studies showed that either the essential oil or β-caryophyllene presented rapid bacterial killing (4 h for S. aureus) and fungicidal effect (2-4 h for F. solani); however, both displayed weak free radical scavenger capacity. The cytotoxic activity exhibited a prominent selective effect against hepatoma cancer cells (IC50 value =63.7 μg/mL) compared with normal fibroblasts (IC50 value =195.0 μg/mL), whereas the β-caryophyllene showed low cytotoxicity.

DISCUSSION AND CONCLUSION

The experimental data suggest that the activities of M. paniculata essential oil are due to the synergistic action among its components.

Murraya paniculata (L.) (Orange Jasmine): Potential Nutraceuticals with Ameliorative Effect in Alloxan-Induced Diabetic Rats

Orange jasmine, Murraya paniculata (Rutaceae), is a plant from India widely used in folk medicine as antinociceptive, antiinflammatory, and antioxidant. Although oral hypoglycemic agents and insulin are the mainstays of treatment of diabetes mellitus (DM), there is a significant demand for new natural products to reduce the development of diabetic complications. Alloxan-induced diabetic rats were treated for 60 days with a hydroalcoholic extract of M. paniculata (MPE), at doses of 100, 200, and 400 mg/kg. MPE decreased glycemia and also cholesterol and triglyceride levels, starting 1 week after treatments, as compared with the same group before treatments. Glucose values were reduced toward normality after 1 week of treatment. MPE hypoglycemic effects were potentiated by glibenclamide and metformin. MPE also decreased fructosamine and glycated hemoglobin values. MPE reduced diabetes-induced morphological alterations of the kidney, pancreas, and liver. MPE acts similarly to glibenclamide and metformin, and its glucose-lowering action is partly a consequence of ATP-sensitive K⁺ channel inhibition. MPE may be a potential therapeutic alternative for the treatment of diabetes and its complications. Copyright © 2017 John Wiley & Sons, Ltd.

Metformin ameliorates diabetic nephropathy in a rat model of low-dose streptozotocin-induced diabetes

The present study aimed to explore the renoprotective effect of metformin on diabetic nephropathy in type 2 diabetic rats. A rat model of type 2 diabetic nephropathy (T2DN) was successfully induced via a high-fat diet combined with a single low-dose of streptozotocin. Metformin was administered intragastrically for 13 weeks, and fasting blood glucose (FBG), total cholesterol (TC), triglycerides (TG), HDL-c, LDL-c, urinary and serum creatinine levels were subsequently examined at the end of administration. Renal function was determined after the treatment protocol. Expression levels of transforming growth factor (TGF)-β1 and connective tissue growth factor (CTGF) were assessed via immunohistochemical analysis. Superoxide dismutase activity, malondialdehyde content and glutathione peroxidase levels were assessed in kidney tissues using commercially available kits. The results of the present study demonstrated that metformin administration significantly decreased the levels of serum blood urea nitrogen, serum creatinine, creatinine clearance, urinary albumin excretion and fasting blood glucose in rats with T2DN. Furthermore, TG, TC and LDL-c levels were significantly decreased following metformin treatment, whereas HDL-c was increased. Metformin treatment significantly increased SOD activity and significantly decreased malondialdehyde levels, as compared with the model group. It was also demonstrated that metformin administration significantly decreased the expression levels of TGF-β1 and attenuated the morphological changes associated with T2DN in rats. These data clearly demonstrated the renoprotective effects of metformin against the development and progression of T2DN in rats. The underlying mechanism of this protective effect may be associated with glycemic control, lipid metabolism, and anti-oxidative and anti-inflammatory functions.

Structured DAG oil ameliorates renal injury in streptozotocin-induced diabetic rats through inhibition of NF-κB and activation of Nrf2 pathway

Accumulating evidence suggested that inflammatory processes are involved in the development of diabetic nephropathy (DN). Here, we have tested the hypothesis that Caprylic Acid (Cy)-diacylglycerol (DAG) oil (Cy-DAG), a novel structurally formulated lipid with high nutritional value, ameliorated DN in streptozotocin (STZ)-induced diabetic rats through the anti-inflammatory mechanisms. Basic hematological, biochemical parameters, immunoblotting, immunofluorescence and flow cytometry analysis were performed to observe the anti-inflammatory potential of Cy-DAG oil. The data revealed that STZ significantly increased the renal oxidative stress markers and decreased the levels of renal enzymatic and non-enzymatic antioxidants. Moreover, renal nitric oxide (NO), tissue necrosis factor-α (TNF-α), interleukin-6 (IL-6) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) were also increased in the renal tissue of STZ-treated rats. Further, DAG oil pretreatment produced a significant improvement in renal antioxidant status, reduced the lipid peroxidation and the levels of inflammatory markers in STZ-treated kidney. Similarly, results of protein expression showed that DAG oil pretreatment normalized the renal expression of Nrf2/Keap1 and its downstream regulatory proteins in STZ-treated condition. Immunohistochemical observations provided further evidence that DAG oil effectively protected the kidney from STZ-mediated oxidative damage. These results suggested that the DAG oil ameliorated STZ-induced oxidative renal injury by the activation of AKT/Nrf2/HO-1 pathway and the inhibition of ROS/MAPK/NF-κB pathway.

Oxidative Stress Parameters and Erythrocyte Membrane Adenosine Triphosphatase Activities in Streptozotocin-induced Diabetic Rats Administered Aqueous Preparation of Kalanchoe Pinnata Leaves

Background:

Diabetes mellitus is a chronic metabolic disease that according to the World Health Organization affects more than 382 million people. The rise in diabetes mellitus coupled with the lack of an effective treatment has led many to investigate medicinal plants to identify a viable alternative.

Objective:

To evaluate red blood cell (RBC) membrane adenosine triphosphatase (ATPase) activities and antioxidant levels in streptozotocin-induced diabetic rats administered aqueous preparation of Kalanchoe pinnata leaves.

Materials and Methods:

Diabetes mellitus was induced in rats by a single administration of streptozotocin (60 mg/kg). Diabetic rats were then treated with aqueous K. pinnata preparation (three mature leaves ~ 9.96 g/70 kg body weight or about 0.14 g/kg body weight/day) for 30 days. Serum glucose, RBC membrane ATPase activities, and antioxidant levels were determined.

Results:

We noted weight loss and reduced food consumption in the treated diabetic group. Serum glucose levels were reduced in the treated diabetic group compared to the other groups. Superoxide dismutase activity and glutathione levels were not significantly elevated in the treated group compared to the diabetic group. However, serum catalase activity was significantly (P < 0.05) increased in the treated diabetic group compared to the other groups. Serum thiobarbituric acid reactive substances were not significantly altered among the groups. There was a significant (P < 0.05) increase in Mg²⁺ ATPase activity and a nonsignificant increase in Na⁺/K⁺ ATPase activity in the RBC membrane of the treated diabetic group compared to the diabetic group.

Conclusion:

The consumption of aqueous preparation of K. pinnata may accrue benefits in the management of diabetes by lowering oxidative stress often associated with the disease and improving the availability of cellular magnesium through an increase in the magnesium ATPase pump in the RBC membrane for increased cellular metabolism of glucose through the glycolytic pathway.

SUMMARY

We noted weight loss and reduced food consumption in the diabetic rats treated with K. pinnata preparation

Serum glucose levels were reduced in diabetic rats treated with K. pinnata preparation

Serum catalase activity was significantly (P < 0.05) increased in diabetic rats treated with K. pinnata preparation

We also noted a significant (P < 0.05) increase in Mg²⁺ ATPase activity in the RBC membranes of diabetic rats treated with K. pinnata preparation

Overall, the consumption of aqueous preparation of K. pinnata lowered oxidative stress often associated with diabetes and improved availability of cellular magnesium through an increase in magnesium ATPase pump in the RBC membrane.

Conjugated metabolites represent the major circulating forms of Abelmoschus manihot in vivo and show an altered pharmacokinetic profile in renal pathology

CONTEXT

The nephron-protective efficacy of Abelmoschus manihot (Linn.) Medicus (Malvaceae) has been proved by randomized controlled clinical trial.

OBJECTIVE

Flavonoids are main active components of A. manihot, which can be transformed into glucuronide/sulfate conjugates in vivo. Exploring the pharmacokinetic profile of these conjugates is necessary to further elucidate the mechanism of action.

MATERIAL AND METHOD

Flavonoid fraction of A. manihot (FFA) was extracted from A. manihot flower with ethanol. FFA (400 mg/kg) was orally given to normal rats and chronic kidney disease (CKD) model rats. Blood samples were collected at 5, 15, 30, 45, 60, 90, 120, 240, 360, and 720 min after administration. The plasma concentrations of quercetin and isorhamnetin glucuronide/sulfate conjugates were analyzed by UPLC-MS/MS.

RESULTS

In normal rats, AUC of quercetin-glucuronide conjugates, isorhamnetin-glucuronide conjugates, quercetin-sulfate conjugates, and isorhamnetin-sulfate conjugates was 459.45 ± 192.70, 1153.01 ± 697.04, 417.81 ± 220.31, and 2475.19 ± 1085.22 μmol h/L, respectively. While AUC of quercetin and isorhamnetin was 5.47 ± 2.54 and 30.73 ± 25.95 μmol h/L. AUC of the glucuronide-sulfate conjugates of quercetin and isorhamnetin is 125-times higher than that of aglycone (quercetin and isorhamnetin), showing that glucuronide/sulfate conjugates represent the major circulating forms of A. manihot flavonoid in vivo. AUC of isorhamnetin-glucuronide conjugates and quercetin-sulfate conjugates was 719.65 ± 619.22 and 275.49 ± 1 60.95 μmol h/L, indicating that less conjugated metabolites were formed in CKD rats compared with normal rats. The ratio of AUCglucuronide/sulfate/AUCaglycone decreased from 125 to 104, which implied the impaired phase II metabolism ability in CKD rat.

DISCUSSION AND CONCLUSION

Glucuronide-sulfate conjugates provide an important clue for further elucidating the activity of conjugated metabolites and their relationship with the nephroprotective efficacy of A. manihot. It is necessary to take caution when extrapolating pharmacokinetics parameters from healthy animals in designing pharmacological studies.

Effect of strawberry (Fragaria × ananassa) leaf extract on diabetic nephropathy in rats

Diabetic nephropathy is a clinical syndrome characterized by albuminuria, hypertension and progressive renal insufficiency. The aim of this study was to investigate the effect of strawberry (Fragaria × ananassa) leaf extract on diabetic nephropathy in rats. Streptozotocin (STZ) diabetic rats were orally treated with three doses (50, 100 and 200 mg/kg) of strawberry leaf extract for 30 days. Nephropathy biomarkers in plasma and kidney were examined at the end of the experiment. The three doses of strawberry leaf extract significantly decreased the levels of blood glucose, urea nitrogen, plasma creatinine, kidney injury molecule (Kim)-1, renal malondialdehyde (MDA), tumour necrosis factor alpha (TNF-α), interleukin (IL)- 6 and caspase-3 in diabetic rats. Meanwhile, the levels of plasma insulin, albumin, uric acid, renal catalase (CAT), superoxide dismutase (SOD) and vascular endothelial growth factor A (VEGF-A) were significantly elevated in diabetic rats treated with strawberry leaf extract. These results indicate the role of strawberry leaves extract as anti-diabetic, antioxidant, anti-inflammatory and anti-apoptosis in diabetic nephropathy.

A flavonoid fraction purified from Rutaceae aurantiae (Daflon(R)) inhibiting AGE formation, reduces urinary albumin clearance and corrects hypoalbuminemia in normotensive and hypertensive diabetic rats

AIM

Advanced glycation endproducts (AGEs) have been shown to contribute to alteration of glomerular permselectivity to proteins in diabetes. Oxidative stress is required for AGE formation. Therefore we studied the effect of an antioxidant micronized purified flavonoid fraction (MPFF, Daflon(R) 500 mg), on urinary albumin clearance in diabetic rats.

METHODS

Hyperglycaemia was induced by streptozotocin 55 mg/kg IM at days 0 and 7 in normotensive Wistar rats (NWR, diabetes duration 5 months) or hypertensive Wistar Kyoto rats (SHR, diabetes duration 2 months). MPFF was administered at 300 mg/kg/day, from day -2 until sacrifice.

RESULTS

After 5 months of diabetes in NWR, MPFF reduced albumin clearance from 729±92 to 392±60 nl/min/kg, p<0.01, and restored albuminemia from 20.4±0.9 to 24.0±1 g/l, p<0.05; albumin fractional clearance was significantly diminished in the flavonoid-treated diabetic rats (0.360±0.037‰ versus 1.335±0.430‰ in the diabetic controls, p<0.001); MPFF did not significantly modify blood glucose and plasma fructosamine levels. After 2 months of diabetes in SHR, MPFF reduced albumin clearance from 243±121 to 101±47 nl/min/kg, p<0.05, and restored albuminemia from 21.1±1.6 to 26.7±2.2 g/l (p<0.05); MPFF also decreased plasma fluorescence characteristic of AGEs (p<0.02). Besides hesperetin, a main metabolite of MPFF recovered in plasma, inhibited in vitro the formation of the crosslinking AGE pentosidine in collagen incubated with high glucose (p<0.001).

CONCLUSION

Our results confirm the role of glycoxidative stress in diabetic nephropathy. MPFF might be useful as complementary treatment for preventing diabetic microangiopathy.