Protective effect of vanillic acid against diabetes and diabetic nephropathy by attenuating oxidative stress and upregulation of NF-κB, TNF-α and COX-2 proteins in rats

Vanillic acid ameliorates diethyl phthalate and bisphenol S-induced oxidative stress and neuroinflammation in the hippocampus of experimental rats

Long-term adverse effects on human health are caused by exogenous compounds that alter the functions of biological systems, especially neuroendocrine disruptors like diethyl phthalate (DEP) and bisphenol S (BPS). Although vanillic acid (VA) has pertinent neuropharmacological characteristics, its effect against DEP + BPS-induced neurotoxicity has not been explored. This study proposed that VA may offer protection against the neurotoxicity caused by DEP + BPS. Thirty male Wistar rats were randomly distributed across five groups: a control group receiving DMSO, a group exposed to a mixture of BPS and DEP, two BPS + DEP-exposed groups treated with VA at doses of 25 mg/kg or 50 mg/kg, and a nonexposed group treated with 50 mg VA/kg. After 21 days, the hippocampal tissues were processed for biochemical analyses. Our results indicate that exposure to DEP + BPS upregulated neurosignaling mediators (NTPDase, ADA, MAO-A, and Ca2+), inhibited others (AChE and Ca2+/Mg2+-ATPase), decreased hippocampus antioxidants (GSH, GPx, CAT, and SOD), and elevated markers of oxidative stress/damage (NO, H2O2, MDA, and AOPP). AR, BAX, TNF-α, BAK1, and IL-1β expressions were upregulated, while IL-10 and BDNF expressions were downregulated. NF-κB and caspase-3/9 pathways were also upregulated. Co-treatment with vanillic acid remarkably precluded these neurotoxic outcomes by improving neurosignaling, augmenting antioxidant status, abrogating oxidative damage, inflammation (TNF-α, IL-1β), and apoptosis (BAX, BAK1, caspase-3/9). Vanillic acid also restored IL-10 and BDNF levels, thereby exhibiting neuroprotective effects, corroborated by histological examinations. We posit vanillic acid as a safe and effective therapeutic agent against neurotoxicity occasioned by exposure to neuroendocrine disruptors.

Evaluation of the therapeutic potential of novel nanoparticle formulations of glutathione and virgin coconut oil in an experimental model of carbon tetrachloride-induced liver failure

BACKGROUND

Acute liver failure (ALF) is a critical condition characterized by rapid liver dysfunction, leading to high mortality rates. Current treatments are limited, primarily supportive, and often require liver transplantation. This study investigates the potential of a novel nanoparticle formulation of glutathione (GSH) and virgin coconut oil (VCO) alone and in combination to enhance therapeutic outcomes in a rat model of ALF induced by orogastric carbon tetrachloride (CCl4).

METHODS

The study employed adult male Albino rats divided into ten groups, with ALF induced via a single oral dose of CCl4. Various treatment regimens were administered over seven days, including conventional and nanoparticle forms of GSH and VCO and their combinations. The efficacy of treatments was evaluated through biochemical analysis of liver function markers, oxidative stress indicators, inflammatory biomarkers, and histopathological examinations. Nanoparticles were synthesized using established methods, and characterization techniques were employed to ensure their quality and properties.

RESULTS

The nanoparticle formulations significantly improved liver function, as indicated by reduced serum levels of alanine aminotransferase and aspartate aminotransferase, alongside decreased oxidative stress markers such as malondialdehyde. Furthermore, they reduced tumor necrosis factor alpha and interleukin-1 beta inflammatory markers. Histological analysis revealed reduced hepatocellular necrosis and inflammation in treated groups compared to controls. Also, decreased nuclear factor-kappa B was detected by immunohistochemical analysis.

CONCLUSION

The findings show that the nanoparticle mixture of GSH and VCO effectively reduces liver damage in ALF. This suggests a promising drug-based approach for improving liver regeneration and protection. This innovative strategy may pave the way for new therapeutic interventions in the management of ALF.

Impacts of Plu kaow (Houttuynia cordata Thunb.) Ethanolic Extract on Diabetes and Dyslipidemia in STZ Induced Diabetic Rats: Phytochemical Profiling, Cheminformatics Analyses, and Molecular Docking Studies

The increasing prevalence of diabetes and dyslipidemia poses significant health challenges, impacting millions of people globally and leading to high rates of illness and death. This study aimed to explore the potential antidiabetic and hypolipidemic effects of Plu kaow (Houttuynia cordata Thunb.) ethanolic extract (PK) in streptozotocin (STZ) induced diabetic rats, focusing on its molecular mechanisms. Diabetes was induced in fasting Long Evans rats using streptozotocin (65 mg/kg b. w.), with glibenclamide (5 mg/kg/day) used as the standard experimental drug. The treated groups received oral supplementation of PK (500 mg/kg/day) for 28 days. The study evaluated blood glucose levels, lipid status, body weight, liver, kidney, and heart function biomarkers, antioxidant activity, and histological examination of various organs. Additionally, untargeted metabolomics, cheminformatics, and molecular docking were employed to elucidate the probable mechanisms of action of PK. Based on metabolomic profiling data, the PK was found to contain various putative antidiabetic agents such as kaempferol 7-neohesperidoside, isochlorogenic acid C, rutin, datiscin, and diosmin and they have been proposed to significantly (p < 0.001) reduce blood glucose levels and modulated hyperlipidemia. PK also improved the tested liver, kidney, and heart function biomarkers and reversed damage to normal pancreatic, liver, kidney, and heart cells in histological analysis. In conclusion, PK shows promise as a potential treatment or management option for diabetes and hyperlipidemia, as well as their associated complications in diabetic rats.

Barleriside A, an aryl hydrocarbon receptor antagonist, ameliorates podocyte injury through inhibiting oxidative stress and inflammation

Introduction

Increasing evidence shows that hyperactive aryl hydrocarbon receptor (AHR) signalling is involved in renal disease. However, no currently available intervention strategy is effective in halting disease progression by targeting the AHR signalling. Our previous study showed that barleriside A (BSA), a major component of Plantaginis semen, exhibits renoprotective effects.

Methods

In this study, we determined the effects of BSA on AHR expression in 5/6 nephrectomized (NX) rats. We further determined the effect of BSA on AHR, nuclear factor kappa B (NF-ƙB), and the nuclear factor erythroid 2-related factor 2 (Nrf2) signalling cascade in zymosan-activated serum (ZAS)-stimulated MPC5 cells.

Results

BSA treatment improved renal function and inhibited intrarenal nuclear AHR protein expression in NX-treated rats. BSA mitigated podocyte lesions and suppressed AHR mRNA and protein expression in ZAS-stimulated MPC5 cells. BSA inhibited inflammation by improving the NF-ƙB and Nrf2 pathways in ZAS-stimulated MPC5 cells. However, BSA did not markedly upregulate the expression of podocyte-specific proteins in the ZAS-mediated MPC5 cells treated with CH223191 or AHR siRNA compared to untreated ZAS-induced MPC5 cells. Similarly, the inhibitory effects of BSA on nuclear NF-ƙB p65, Nrf2, and AHR, as well as cytoplasmic cyclooxygenase-2, heme oxygenase-1, and AHR, were partially abolished in ZAS-induced MPC5 cells treated with CH223191 or AHRsiRNA compared with untreated ZAS-induced MPC5 cells. These results indicated that BSA attenuated the inflammatory response, partly by inhibiting AHR signalling.

Discussion

Both pharmacological and siNRA findings suggested that BSA mitigated podocyte lesions by improving the NF-ƙB and Nrf2 pathways via inhibiting AHR signalling. Therefore, BSA is a high-affinity AHR antagonist that abolishes oxidative stress and inflammation.

Fungal Laccases and Fumonisin Decontamination in Co-Products of Bioethanol from Maize

Maize (Zea mays L.) may be infected by Fusarium verticillioides and F. proliferatum, and consequently contaminated with fumonisins (FBs), as well as the co-products of bioethanol intended for animal feed. Laccase enzymes have a wide industrial application such as mycotoxin degradation. The aims were to isolate and identify fungal laccase-producing strains, to evaluate laccase production, to determine the enzymatic stability under fermentation conditions, and to analyse the effectiveness in vitro of enzymatic extracts (EEs) containing laccases in degrading FB1. Strains belonging to Funalia trogii, Phellinus tuberculosus, Pleurotus ostreatus, Pycnoporus sanguineus and Trametes gallica species showed laccase activity. Different isoforms of laccases were detected depending on the evaluated species. For the FB1 decontamination assays, four enzymatic activities (5, 10, 15 and 20 U/mL) were tested, in the absence and presence of vanillic acid (VA) and 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) as redox mediators (1 and 10 mM). Trametes gallica B4-IMICO-RC EE was the most effective strain in buffer, achieving a 60% of FB1 reduction. Laccases included in EEs remained stable at different alcoholic degrees in maize steep liquor (MSL), but no significant FB1 reduction was observed under the conditions evaluated using MSL. This study demonstrate that although laccases could be good candidates for the development of a strategy to reduce FB1, further studies are necessary to optimise this process in MSL.

Ameliorative effect of vanillic acid against scopolamine-induced learning and memory impairment in rat via attenuation of oxidative stress and dysfunctional synaptic plasticity

Alzheimer's disease (AD) is characterized by cognitive impairment, loss of learning and memory, and abnormal behaviors. Scopolamine (SCOP) is a non-selective antagonist of muscarinic acetylcholine receptors that exhibits the behavioral and molecular hallmarks of AD. Vanillic acid (VA), a phenolic compound, is obtained from the roots of a traditional plant called Angelica sinensis, and has several pharmacologic effects, including antimicrobial, anti-inflammatory, anti-angiogenic, anti-metastatic, and antioxidant properties. Nevertheless, VA's neuroprotective potential associated with the memory has not been thoroughly investigated. Therefore, this study investigated whether VA treatment has an ameliorative effect on the learning and memory impairment induced by SCOP in rats. Behavioral experiments were utilized to assess the learning and memory performance associated with the hippocampus. Using western blotting analysis and assay kits, the neuronal damage, oxidative stress, and acetylcholinesterase activity responses of hippocampus were evaluated. Additionally, the measurement of long-term potentiation was used to determine the function of synaptic plasticity in organotypic hippocampal slice cultures. In addition, the synaptic vesicles' density and the length and width of the postsynaptic density were evaluated using electron microscopy. Consequently, the behavioral, biochemical, electrophysiological, and ultrastructural analyses revealed that VA treatment prevents learning and memory impairments caused by SCOP in rats. The study's findings suggest that VA has a neuroprotective effect on SCOP-induced learning and memory impairment linked to the hippocampal cholinergic system, oxidative damage, and synaptic plasticity. Therefore, VA may be a prospective therapeutic agent for treating AD.

Emerging Roles and Therapeutic Applications of Arachidonic Acid Pathways in Cardiometabolic Diseases

Cardiometabolic disease has become a major health burden worldwide, with sharply increasing prevalence but highly limited therapeutic interventions. Emerging evidence has revealed that arachidonic acid derivatives and pathway factors link metabolic disorders to cardiovascular risks and intimately participate in the progression and severity of cardiometabolic diseases. In this review, we systemically summarized and updated the biological functions of arachidonic acid pathways in cardiometabolic diseases, mainly focusing on heart failure, hypertension, atherosclerosis, nonalcoholic fatty liver disease, obesity, and diabetes. We further discussed the cellular and molecular mechanisms of arachidonic acid pathway-mediated regulation of cardiometabolic diseases and highlighted the emerging clinical advances to improve these pathological conditions by targeting arachidonic acid metabolites and pathway factors.

Hesperidin, vanillic acid, and sinapic acid attenuate atorvastatin-induced mitochondrial dysfunction via inhibition of mitochondrial swelling and maintenance of mitochondrial function in pancreas isolated mitochondria

It has been reported that lipophilic statins such as atorvastatin can more readily penetrate into β-cells and reach the mitochondria, resulting in mitochondrial dysfunction, oxidative stress, decrease in insulin release. Many studies have shown that natural products can protect mitochondrial dysfunction induced by drug in different tissue. We aimed to explore mitochondrial protection potency of hesperidin, vanillic acid, and sinapic acid as natural compounds against mitochondrial dysfunction induced by atorvastatin in pancreas isolated mitochondria. Mitochondria were isolated form rat pancreas and directly treated with toxic concentration of atorvastatin (500 µM) in presence of various concentrations hesperidin, vanillic acid, and sinapic acid (1, 10, and 100 µM) separately. Mitochondrial toxicity parameters such as the reactive oxygen species (ROS) formation, succinate dehydrogenases (SDH) activity, mitochondrial swelling, depletion of glutathione (GSH), mitochondrial membrane potential (MMP) collapse, and malondialdehyde (MDA) production were measured. Our findings demonstrated that atorvastatin directly induced mitochondrial toxicity at concentration of 500 μM and higher in pancreatic mitochondria. Except MDA, atorvastatin caused significantly reduction in SDH activity, mitochondrial swelling, ROS formation, depletion of GSH, and collapse of MMP. While, our data showed that all three protective compounds at low concentrations ameliorated atorvastatin-induced mitochondrial dysfunction with the increase of SDH activity, improvement of mitochondrial swelling, MMP collapse and mitochondrial GSH, and reduction of ROS formation. We can conclude that hesperidin, vanillic acid, and sinapic acid can directly reverse the toxic of atorvastatin in rat pancreas isolated mitochondria, which may be beneficial for protection against diabetogenic-induced mitochondrial dysfunction in pancreatic β-cells.

Selective Degradation of Technically Relevant Lignin to Vanillic Acid and Protocatechuic Acid

A new and practical method for the thermal degradation of technically relevant bio-based lignin is presented. By heating a solution of lignin in highly concentrated caustic potash, vanillic acid is almost exclusively obtained in yields up to 10.6 wt %. By altering the reaction parameters, the selectivity of the reaction can be shifted towards the demethylation product, protocatechuic acid, which is obtained in a yield of 6.9 wt %. Furthermore, the procedure was applicable to different types of Kraft and organosolv lignin. To create an economically feasible process, ion exchange resins were used for the work-up of the highly caustic reaction media without neutralizing the complete mixture. By the selective removal of the desired vanillic acid from the caustic potash, this alkaline media could directly be reused for at least 5 further lignin degradations without significant loss of yield.

Exploring Folklore Ecuadorian Medicinal Plants and Their Bioactive Components Focusing on Antidiabetic Potential: An Overview

Diabetes mellitus (DM) is a global health concern characterized by a deficiency in insulin production. Considering the systemic toxicity and limited efficacy associated with current antidiabetic medications, there is the utmost need for natural, plant-based alternatives. Herbal medicines have experienced exponential growth in popularity globally in recent years for their natural origins and minimal side effects. Ecuador has a rich cultural history in ethnobotany that plays a crucial role in its people's lives. This study identifies 27 Ecuadorian medicinal plants that are traditionally used for diabetes treatment and are prepared through infusion, decoction, or juice, or are ingested in their raw forms. Among them, 22 plants have demonstrated hypoglycemic or anti-hyperglycemic properties that are rich with bioactive phytochemicals, which was confirmed in several in vitro and in vivo studies. However, Bryophyllum gastonis-bonnieri, Costus villosissimus, Juglans neotropica, Pithecellobium excelsum, and Myroxylon peruiferum, which were extensively used in traditional medicine preparation in Ecuador for many decades to treat diabetes, are lacking in pharmacological elucidation. The Ecuadorian medicinal plants used to treat diabetes have been found to have several bioactive compounds such as flavonoids, phenolics, fatty acids, aldehydes, and terpenoids that are mainly responsible for reducing blood sugar levels and oxidative stress, regulating intestinal function, improving insulin resistance, inhibiting α-amylase and α-glucosidase, lowering gluconeogenic enzymes, stimulating glucose uptake mechanisms, and playing an important role in glucose and lipid metabolism. However, there is a substantial lack of integrated approaches between the existing ethnomedicinal practices and pharmacological research. Therefore, this review aims to discuss and explore the traditional medicinal plants used in Ecuador for treating DM and their bioactive phytochemicals, which are mainly responsible for their antidiabetic properties. We believe that the use of Ecuadorian herbal medicine in a scientifically sound way can substantially benefit the local economy and industries seeking natural products.

NF-ĸB axis in diabetic neuropathy, cardiomyopathy and nephropathy: A roadmap from molecular intervention to therapeutic strategies

Diabetes mellitus (DM) is a metabolic illness defined by elevated blood glucose levels, mediating various tissue alterations, including the dysfunction of vital organs. Diabetes mellitus (DM) can lead to many consequences that specifically affect the brain, heart, and kidneys. These issues are known as neuropathy, cardiomyopathy, and nephropathy, respectively. Inflammation is acknowledged as a pivotal biological mechanism that contributes to the development of various diabetes consequences. NF-κB modulates inflammation and the immune system at the cellular level. Its abnormal regulation has been identified in several clinical situations, including cancer, inflammatory bowel illnesses, cardiovascular diseases, and Diabetes Mellitus (DM). The purpose of this review is to evaluate the potential impact of NF-κB on complications associated with DM. Enhanced NF-κB activity promotes inflammation, resulting in cellular harm and compromised organ performance. Phytochemicals, which are therapeutic molecules, can potentially decline the NF-κB level, therefore alleviating inflammation and the progression of problems correlated with DM. More importantly, the regulation of NF-κB can be influenced by various factors, such as TLR4 in DM. Highlighting these factors can facilitate the development of novel therapies in the future.

Causal relationship between type 2 diabetes mellitus and aortic dissection: insights from two-sample Mendelian randomization and mediation analysis

Objective

Some evidence suggests a reduced prevalence of type 2 diabetes mellitus (T2DM) in patients with aortic dissection (AD), a catastrophic cardiovascular illness, compared to general population. However, the conclusions were inconsistent, and the causal relationship between T2DM and AD remains unclear.

Methods

In this study, we aimed to explore the causal relationship between T2DM and AD using bidirectional Mendelian randomization (MR) analysis. Mediation MR analysis was conducted to explore and quantify the possible mediation effects of 1400 metabolites in T2DM and AD.

Results

The results of 26 datasets showed no causal relationship between T2DM and AD (P>0.05). Only one dataset (ebi-a-GCST90006934) showed that T2DM was a protective factor for AD (I9-AORTDIS) (OR=0.815, 95%CI: 0.692-0.960, P=0.014), and did not show horizontal pleiotropy (P=0.808) and heterogeneity (P=0.525). Vanillic acid glycine plays a mediator in the causal relationship between T2DM and AD. The mediator effect for vanillic acid glycine levels was -0.023 (95%CI: -0.066-0.021).

Conclusion

From the perspective of MR analysis, there might not be a causal relationship between T2DM and AD, and T2DM might not be a protective factor for AD. If a causal relationship does exist between T2DM and AD, with T2DM serving as a protective factor, vanillic acid glycine may act as a mediator and enhance such a protective effect.

Vanillic acid restores homeostasis of intestinal epithelium in colitis through inhibiting CA9/STIM1-mediated ferroptosis

The damage of integrated epithelial epithelium is a key pathogenic factor and closely associated with the recurrence of ulcerative colitis (UC). Here, we reported that vanillic acid (VA) exerted potent therapeutic effects on DSS-induced colitis by restoring intestinal epithelium homeostasis via the inhibition of ferroptosis. By the CETSA assay and DARTS assay, we identified carbonic anhydrase IX (CAIX, CA9) as the direct target of VA. The binding of VA to CA9 causes insulin-induced gene-2 (INSIG2) to interact with stromal interaction molecule 1 (STIM1), rather than SREBP cleavage-activating protein (SCAP), leading to the translocation of SCAP-SREBP1 from the endoplasmic reticulum (ER) to the Golgi apparatus for cleavage into mature SREBP1. The activation of SREBP1 induced by VA then significantly facilitated the transcription of stearoyl-CoA desaturase 1 (SCD1) to exert an inhibitory effect on ferroptosis. By inhibiting the excessive death of intestinal epithelial cells caused by ferroptosis, VA effectively preserved the integrity of intestinal barrier and prevented the progression of unresolved inflammation. In conclusion, our study demonstrated that VA could alleviate colitis by restoring intestinal epithelium homeostasis through CA9/STIM1-mediated inhibition of ferroptosis, providing a promising therapeutic candidate for UC.

Phytochemical profiling, toxicity studies, wound healing, analgesic and anti-inflammatory activities of Musa paradisiaca L. Musaceae (Plantain) stem extract in rats

ETHNOPHARMACOLOGICAL RELEVANCE

The stem of Musa paradisiaca (plantain) has found application in traditional medicine for the treatment of diabetes, inflammation, ulcers and wound injuries.

AIM OF THE STUDY

This study investigated the phytochemical composition, toxicity profile, wound healing, anti-inflammatory and analgesic effects of aqueous Musa paradisiaca stem extract (AMPSE) in rats.

METHODS

Phytochemical analysis of methanol-MPSE was performed by gas chromatography-mass spectrometry (GC-MS). Acute toxicity testing was carried out through oral administration of a single dose of AMPSE up to 5 g/kg. Four separate groups of rats were used for the subacute toxicity testing (n = 6). Group 1 served as a normal control and did not receive AMPSE, groups 2-4 received AMPSE daily by gavage for 28 days. In the experiments with excision and incision wounds, the rats were treated with 10 w/w AMPS extract. The anti-inflammatory and analgesic effects of AMPSE were assessed using egg albumin-induced paw oedema and acetic acid-induced writhing methods, respectively. For the subacute, anti-inflammatory and analgesic studies, AMPSE was administered to the experimental rats at doses of 300, 600 and 900 mg/kg body weight.

RESULTS

Bioactive compounds identified include β-sitisterol, n-hexadecanoic acid, octadecanoic acid, diethyl sulfate, p-hydroxynorephedrine, phenylephrine, nor-pseudoephedrine, metaraminol, pseudoephedrine and vanillic acid. No signs of toxicity and no deaths were observed in all the groups. For the groups treated with AMPSE for 28 days, a significant reduction in alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, urea, sodium, chloride, total cholesterol, triglycerides, and low-density lipoprotein cholesterol were observed while high density lipoprotein cholesterol, glutathione and superoxide dismutase increased compared to control (p < 0.05). In wound healing experiments, AMPSE showed greater percent wound contraction and wound resistance fracture compared to the povidone-iodine (PI) treated and control groups. Treatment with 900 mg/kg AMPSE resulted in significant (p < 0.05) anti-inflammatory and analgesic effects compared to the control.

CONCLUSION

This study shows that AMPSE is not toxic but contains biologically active compounds with hepatoprotective, anti-inflammatory, lipid-lowering and wound-healing effects. Treatment of rats with AMPSE has shown that AMPSE has anti-inflammatory, analgesic, hepatoprotective, lipid-lowering and wound-healing effects, supporting its therapeutic use in ethnomedicine.

Effect of In Vitro Micropropagation on the Chemical, Antioxidant, and Biological Characteristics of Senecio nutans Sch. Bip., an Endemic Plant of the Atacama Desert Andean Region

The species Senecio nutans Sch. Bip., commonly called "chachacoma", is widely used as a medicinal plant by the Andean communities of Northern Chile. Ethanolic extracts of S. nutans and the main compound, 4-hydroxy-3-(3-methyl-2-butenyl) acetophenone, have shown interesting biological activity. However, due to the high-altitude areas where this species is found, access to S. nutans is very limited. Due to the latter, in this work, we carried out micropropagation in vitro and ex vitro adaptation techniques as an alternative for the massive multiplication, conservation, and in vitro production of high-value metabolites from this plant. The micropropagation and ex vitro adaptation techniques were successfully employed, and UHPLC-DAD analysis revealed no significant changes in the phenolic profile, with acetophenone 4 being the most abundant metabolite, whose antioxidant and antibacterial activity was studied. Independently of the applied culture condition, the ethanolic extracts of S. nutans presented high activity against both Gram-positive and Gram-negative bacteria, demonstrating their antimicrobial capacity. This successful initiation of in vitro and ex vitro cultures provides a biotechnological approach for the conservation of S. nutans and ensures a reliable and consistent source of acetophenone 4 as a potential raw material for pharmacological applications.

Underlying mechanisms behind the neuroprotective effect of vanillic acid against diabetes-associated cognitive decline: An in vivo study in a rat model

Hippocampal synaptic dysfunction, oxidative stress, neuroinflammation, and neuronal loss play critical roles in the pathophysiology of diabetes-associated cognitive decline (DACD). The study aimed to investigate the effects of vanillic acid (VA), a phenolic compound, against DACD and explore the potential underlying mechanisms. Following confirmation of diabetes, rats were treated with VA (50 mg/kg/day; P.O.) or insulin (6 IU/rat/day; S.C.) for 8 consecutive weeks. The cognitive performance of the rats was evaluated using passive-avoidance and water-maze tasks. Long-term potentiation (LTP) was induced at hippocampal dentate gyrus (DG) synapses in response to high-frequency stimulation (HFS) applied to the perforant pathway (PP) to evaluate synaptic plasticity. Oxidative stress factors, inflammatory markers, and histological changes were evaluated in the rat hippocampus. This study showed that streptozotocin (STZ)-induced diabetes caused cognitive decline that was associated with inhibition of LTP induction, suppression of enzymatic antioxidant activities, enhanced lipid peroxidation, elevated levels of inflammatory proteins, and neuronal loss. Interestingly, chronic treatment with VA alleviated blood glucose levels, improved cognitive decline, ameliorated LTP impairment, modulated oxidative-antioxidative status, inhibited inflammatory response, and prevented neuronal loss in diabetic rats at a level comparable to insulin therapy. The results suggest that the antihyperglycemic, antioxidative, anti-inflammatory, and neuroplastic properties of VA may be the mechanisms behind its neuroprotective effect against DACD.

Novel drug therapy of acute hepatic failure induced in rats by a combination of tadalafil and Lepidium sativum

BACKGROUND

Hepatocyte death and a systemic inflammatory response are the outcome of a complex chain of events mediated by numerous inflammatory cells and chemical mediators. The point of this study was to find out if tadalafil and/or Lepidium sativum (L. sativum) could help people who have been exposed to carbon tetrachloride (CCL4) and are experiencing acute moderate liver failure. This was especially true when the two were used together.

METHOD AND MATERIALS

To cause mild liver failure 24 h before sacrifice, a single oral dosage of CCL4 (2.5 mL/kg b.w.) (50% in olive oil) was utilized. Furthermore, immunohistochemical expression of nuclear factor kappa B (NF-κB) as well as histological abnormalities were performed on liver tissue.

RESULTS

The results showed that tadalafil and/or L. sativum, especially in combination, performed well to cure acute mild liver failure caused by CCL4. This was demonstrated by a decrease in NF-κB expression in the liver tissue and an improvement in organ damage markers observed in the blood and liver tissues. Furthermore, such therapy reduced interleukin1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) levels in the liver tissue. It's worth noting that the tested combination resulted in greater liver improvement.

CONCLUSIONS

According to the findings, tadalafil and L. sativum, particularly in combination, have the ability to protect the liver from the negative effects of CCL4 exposure. Because of its capacity to improve liver function, restore redox equilibrium, and decrease inflammatory mediators, it is a prospective option for mitigating the negative effects of common environmental pollutants such as CCL4.

Effect and pharmacological mechanism of Salvia miltiorrhiza and its characteristic extracts on diabetic nephropathy

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetic nephropathy (DN) is a severe diabetic microvascular complication with an increasing prevalence rate and lack of effective treatment. Traditional Chinese medicine has been proven to have favorable efficacy on DN, especially Salvia miltiorrhiza Bunge (SM), one of the most critical and conventional herbs in the treatment. Over the past decades, studies have demonstrated that SM is a potential treatment for DN, and the exploration of the underlying mechanism has also received much attention.

AIM OF THIS REVIEW

This review aims to systematically study the efficacy and pharmacological mechanism of SM in the treatment of DN to understand its therapeutic potential more comprehensively.

MATERIALS AND METHODS

Relevant information was sourced from Google Scholar, PubMed, Web of Science, and CNKI databases.

RESULTS

Several clinical trials and systematic reviews have indicated that SM has definite benefits on the kidneys of diabetic patients. And many laboratory studies have further revealed that SM and its characteristic extracts, mainly including salvianolic acids and tanshinones, can exhibit pharmacological activity against DN by the regulation of metabolism, renal hemodynamic, oxidative stress, inflammation, fibrosis, autophagy, et cetera, and several involved signaling pathways, thereby preventing various renal cells from abnormal changes in DN, including endothelial cells, podocytes, epithelial cells, and mesangial cells.

CONCLUSION

As a potential drug for the treatment of DN, SM has multi-component, multi-target, and multi-pathway pharmacological effects. This work will not only verify the satisfactory curative effect of SM in the treatment of DN but also provide helpful insights for the development of new anti-DN drugs and the application of traditional Chinese medicine.

Study of hispidulin in the treatment of uric acid nephropathy based on NF-κB signaling pathway

Uric acid nephropathy (UAN) is caused by purine metabolism disorders. UAN rat models were established in SD rats. The modeling rats received different doses of hispidulin (10, 20, 50 mg/mL). Febuxostat was applied as the positive drug. Serum creatinine, uric acid (UA), and cystatin-C (cys-C), neutrophil gelatinase-associated lipocalin (NGAL), IL-1β, IL-8, TNF-α, and IL-6 in rats were detected. HE staining was done to assess kidney injury. UAN rats possessed prominent levels of serum creatinine, UA, cys-C, and NGAL, which all reduced after hispidulin treatment in a dose-dependent manner. HE staining determined the improvement of kidney injury after treatment, which was comparable to the efficacy of febuxostat. Hispidulin inhibited the release of IL-1β, IL-8, TNF-α, and IL-6 in UAN rats. Hispidulin enhanced autophagy in UAN rats, presenting as ascending LC3II/I ratio and downregulated P62. The increasing trend of inflammasome-related proteins of NLRP3 and Caspase-1 was changeovered by hispidulin. The activation of NF-kB signaling was intercepted by hispidulin in UAN rats. Hispidulin can effectively improve renal function injury caused by UAN in rats. The mechanism may be related to the inhibition of inflammatory response induced by autophagy and activation of NF-κB pathway.

Comparative pharmacokinetic analysis of six major bioactive constituents using UPLC-MS/MS in samples isolated from normal and diabetic nephropathy rats after oral administration of Gushen Jiedu capsule

Berberine, palmatine, physcion, rhein, calycosin-7-O-glucoside, and ferulic acid are six major active consituents that are present in Gushen Jiedu capsule (GSJD) extracts. The aim of this study was to determine the pharmacokinetics of the six active consituents in vivo by a rapid, sensitive, and precise UPLC-MS/MS method, which were compared between normal and diabetic nephropathy (DN) rats. Good separation of the target analytes and internal standards (ketoprofen and puerarin) was obtained on a Waters BEH C18 UPLC column with a mobile phase of 0.1 % formic acid acetonitrile-0.1 % formic acid water. All the calibration curves showed good linearity with a regression coefficient (r2) of ≥ 0.9908. The lower limits of quantification (LLOQ) for berberine, palmatine, physcion, rhein, calycosin-7-O-glucoside, and ferulic acid were 20, 2.5, 20, 20, 2.5, and 2.5 ng/mL, respectively. The relative standard deviations (RSDs) of intra-day and inter-day precision were all within 12.66 %, and the relative errors of intra-day and inter-day accuracy ranged from - 15.00 to 14.93 %. Good extraction recovery and matrix effects were obtained. The stability study confirmed the stability of the six analytes (RSD < 15 %). Finally, the data showed that the pharmacokinetic parameters (especially CLz/F, AUC and Tmax) of the six target analytes in DN rats were significantly different from those in normal rats. PK studies under pathological conditions could provide new thoughts to elucidate the underlying mechanism of GSJD and promote the clinical development of GSJD to treat DN.

Pharmacokinetics, tissue distribution and excretion of six bioactive components from total glucosides picrorhizae rhizoma, as simultaneous determined by a UHPLC-MS/MS method

Total glucosides picrorhizae rhizome (TGPR) is an innovative traditional Chinese medicine, which is a candidate drug for the treatment of nonalcoholic steatohepatitis (NASH). However, there is still lack of deep research on the behaviors of TGPR in vivo. In this study, a reliable, specific, and sensitive liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method has been constructed for simultaneous determination of picroside I, picroside II, vanillic acid, androsin, cinnamic acid and picroside IV, the major active constituents of TGPR, in rat various biological matrices (plasma, tissue, bile, urine and feces) using diphenhydramine hydrochloride and paeoniflorin as the internal standard. All biosamples were prepared using a simple protein precipitation with acetonitrile. Chromatographic separation was achieved on a waters UHPLC® HSS T3 (100×2.1 mm, 1.8 μm) column. The mobile phase consisted of methanol: acetonitrile1(1:1, V/V) and 0.5 mM ammonium formate in water, was employed to separate six components from endogenous interferences. The components were detected with a triple quadrupole mass spectrometer using positive and negative ion multiple reaction monitoring (MRM) mode. The newly developed method was successfully applied to investigate the pharmacokinetics, tissue distribution and excretion of six components in rats. The pharmacokinetic results indicated that the six components in TGPR could be quickly absorbed and slowly eliminated and their bioavailability were less than 12.37%, which implied the poor absorption after intragastric dosing. For tissue distribution, the six components in TGPR were detected in liver and only androsin could penetrate the blood-brain barrier. Meanwhile, the excretion study demonstrated that vanillic acid was mostly excreted as prototype drugs and the remaining five components might be widely metabolized in vivo as the metabolites, the unconverted form was excreted mainly by feces route. The pharmacokinetics, tissue distribution and excretion characteristics of six bioactive components in TGPR were firstly revealed, which will provide references for further clinical application of TGPR as an anti-NASH drug.

Ferroptosis: a new strategy for Chinese herbal medicine treatment of diabetic nephropathy

Diabetic nephropathy (DN) is a serious microvascular complication of diabetes. It has become a leading cause of death in patients with diabetes and end-stage renal disease. Ferroptosis is a newly discovered pattern of programmed cell death. Its main manifestation is the excessive accumulation of intracellular iron ion-dependent lipid peroxides. Recent studies have shown that ferroptosis is an important driving factor in the onset and development of DN. Ferroptosis is closely associated with renal intrinsic cell (including renal tubular epithelial cells, podocytes, and mesangial cells) damage in diabetes. Chinese herbal medicine is widely used in the treatment of DN, with a long history and definite curative effect. Accumulating evidence suggests that Chinese herbal medicine can modulate ferroptosis in renal intrinsic cells and show great potential for improving DN. In this review, we outline the key regulators and pathways of ferroptosis in DN and summarize the herbs, mainly monomers and extracts, that target the inhibition of ferroptosis.

Silencing LncRNA SNHG16 suppresses the diabetic inflammatory response by targeting the miR-212-3p/NF-κB signaling pathway

BACKGROUND

Long noncoding RNAs (LncRNAs) have been identified to play an important role in diabetes. The aim of the present study was to determine the expression and function of small nucleolar RNA host gene 16 (SNHG16) in diabetic inflammation.

METHODS

For the in vitro experiments, quantitative real-time PCR (qRT-PCR), Western blotting and immunofluorescence were used to detect LncRNA SNHG16 expression in the high-glucose state. The potential microRNA sponge target of LncRNA SNHG16, miR-212-3p, was detected by dual-luciferase reporter analysis and qRT-PCR. For the in vivo experiments, glucose changes in mice were detected after si-SNHG16 treatment, and SNHG16 and inflammatory factor expression in kidney tissues were detected by qRT-PCR and immunohistochemistry.

RESULTS

LncRNA SNHG16 was upregulated in diabetic patients, HG-induced THP-1 cells, and diabetic mice. Silencing SNHG16 inhibited the diabetic inflammatory response and the development of diabetic nephropathy. miR-212-3p was found to be directly dependent on LncRNA SNHG16. miR-212-3p could inhibitor P65 phosphorylation in THP-1 cells. The miR-212-3p inhibitor reversed the action of si-SNHG16 in THP-1 cells and induced an inflammatory response in THP-1 cells. LncRNA SNHG16 was also found to be higher in the peripheral blood of diabetic patients than in the normal person. The area under the ROC curve is 0.813.

CONCLUSION

These data suggested that silencing LncRNA SNHG16 suppresses diabetic inflammatory responses by competitively binding miR-212-3p to regulate NF-κB. LncRNA SNHG16 can be used as a novel biomarker for patients with type 2 diabetes.

Attenuation of Oxidative Stress and Regulation of AKT Signaling by Vanillic Acid during Bovine Pre-Implantation Embryo Development

Vanillic acid (VA) has shown antioxidant and anti-inflammatory activities in different cell types, but its biological effects in the context of early embryo development have not yet been clarified. In the current study, the impact of VA supplementation during in vitro maturation (IVM) and/or post-fertilization (in vitro culture; IVC) on redox homeostasis, mitochondrial function, AKT signaling, developmental competence, and the quality of bovine pre-implantation embryos was investigated. The results showed that dual exposure to VA during IVM and late embryo culture (IVC3) significantly improved the blastocyst development rate, reduced oxidative stress, and promoted fatty acid oxidation as well as mitochondrial activity. Additionally, the total numbers of cells and trophectoderm cells per blastocyst were higher in the VA-treated group compared to control (p < 0.05). The RT-qPCR results showed down-regulation of the mRNA of the apoptosis-specific markers and up-regulation of AKT2 and the redox homeostasis-related gene TXN in the treated group. Additionally, the immunofluorescence analysis showed high levels of pAKT-Ser473 and the fatty acid metabolism marker CPT1A in embryos developed following VA treatment. In conclusion, the study reports, for the first time, the embryotrophic effects of VA, and the potential linkage to AKT signaling pathway that could be used as an efficacious protocol in assisted reproductive technologies (ART) to improve human fertility.

Gentisic acid protects against diabetic nephropathy in Nicotinamide-Streptozotocin administered male mice by attenuating oxidative stress and inflammation: The role of miR-200a/Keap1/Nrf2 pathway, renin-angiotensin system (RAS) and NF-кB

Oxidative stress and inflammation play a pivotal role in the pathogenesis of diabetic nephropathy (DN). Local renin-angiotensin systems (RAS) contribute to the pathogenesis and progression of DN by exacerbating oxidative stress and inflammation.Gentisic acid (GA), a phenolic compound and also a metabolite of aspirin, is reported to possess antioxidant and anti-inflammatory properties. However, the protective effects of GA against DN remain to be elucidated. Nicotinamide (110 mg/kg) and streptozotocin (65 mg/kg) were used to induce diabetes in male mice. Oral administration of GA once daily for 2 weeks (100 mg/kg) ameliorated diabetes-induced renal injury by reducing plasma creatinine, urea, blood urea nitrogen, and urinary albuminuria levels. Diabetic mice showed a significant increase in total oxidant status and malondialdehyde, along with decreased catalase, superoxide dismutase, and glutathione peroxidase in the kidney tissue, which was ameliorated in the GA-treated mice. Histopathological analysis showed that GA treatment reduced diabetes-induced renal injury. Furthermore, GA treatment was associated with the downregulation of miR-125b, nuclear factor kappa beta (NF-кB), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and upregulation of interleukin-10 (IL-10), miR-200a, and nuclear factor erythroid 2-related factor 2 (Nrf2) in the renal tissue. GA treatment also downregulated angiotensin-converting enzyme 1 (ACE1), angiotensin II receptor 1 (AT1R), and NADPH oxidase 2 (NOX 2) and upregulated angiotensin-converting enzyme 2 (ACE2). In conclusion, the ameliorative effects of GA against DN may be attributed to its powerful antioxidant and anti-inflammatory properties through the downregulation of NF-кB, upregulation of Nrf2, and modulation of RAS in renal tissue.

Anthocyanins and Vascular Health: A Matter of Metabolites

Anthocyanins are a subgroup of flavonoid polyphenols previously investigated for improving cardiovascular health and preventing the development of endothelial dysfunction. However, their poor bioavailability raises the question of whether the observed biological activity is due to their metabolites. Phenolic metabolites can reach higher plasma concentrations and can persist in the circulation for periods much longer than their original anthocyanin form; therefore, the biological activity and health promoting effects of anthocyanins may differ from their metabolites. To address this, recent studies have facilitated different cell models, in vivo studies and explored physiologically relevant concentrations to better understand their mechanisms of action. The criteria were chosen based on previous reports demonstrating that anthocyanins can improve endothelial function via modulation of the Akt-endothelial nitric oxide synthase pathway and transcription factors Nrf2 and NF-κB, which made it critical to assess the phenolic metabolites' modes of action via these pathways. This review demonstrates how phenolic metabolites differ in bioactivity from their precursor anthocyanin, demonstrating improved endothelial function in response to inflammatory mediators at concentrations that are tolerated in vivo. The review highlights the crucial need for further studies to focus on improving the bioavailability of metabolites in isolation and explore the effect of metabolites in mixtures.

Metabolomics profiling distinctively identified end-stage renal disease patients from chronic kidney disease patients

Chronic kidney disease (CKD) is a serious public health problem characterized by progressive kidney function loss leading to end-stage renal disease (ESRD) that demands dialysis or kidney transplantation. Early detection can prevent or delay progression to ESRD. The study aimed to gain new insights into the perturbed biochemical reactions and to identify novel distinct biomarkers between ESRD and CKD. Serum samples of 32 patients with ESRD (n = 13) and CKD (n = 19) were analyzed using chemical isotope labeling liquid chromatography-mass spectrometry metabolomics approach. A total of 193 metabolites were significantly altered in ESRD compared to CKD and were mainly involved in aminoacyl-tRNA biosynthesis, branched-chain amino acid (BCAA) biosynthesis, taurine metabolism, and tryptophan metabolism. Three kynurenine derivatives, namely, 2-aminobenzoic acid, xanthurenic acid, and hydroxypicolinic acid were upregulated in ESRD compared to CKD due to the significant decrease in glomerular filtration rate with the progression of CKD to ESRD. N-Hydroxy-isoleucine, 2-aminobenzoic acid, and picolinic acid yielded AUC > 0.99 when analyzed using Receiver Operating Characteristic (ROC) analysis. Our findings suggest that inhibiting the kynurenine pathway might be a promising target to delay CKD progression and that metabolites with high discriminative ability might serve as potential prognostic biomarkers to monitor the progression of CKD to ESRD or used in combination with current markers to indicate the status of kidney damage better.

Thai Rat-Tailed Radish Prevents Hepatocarcinogenesis in Rats by Blocking Mutagenicity, Inducing Hepatic Phase II Enzyme, and Decreasing Hepatic Pro-Inflammatory Cytokine Gene Expression

Raphanus sativus L. var. caudatus Alef (RS) is an indigenous Thai plant with nutritional and medicinal values such as anticancer activity, but only in vitro. The chemopreventive effects of RS were, therefore, investigated in the initial stage of hepatocarcinogenesis in rats. Diethylnitrosamine (DEN), a carcinogen, was intraperitoneally injected into rats to induce liver cancer. Along with the DEN injection, either aqueous (RS-H₂O) or dichloromethane (RS-DCM) extract was administered orally. Immunohistochemistry was used to detect glutathione S-transferase placental (GST-P) positive foci and apoptotic cells in rat livers as indicators of initial-stage carcinogenesis. The underlying mechanisms of chemoprevention were investigated with (a) antimutagenic activity, (b) hepatic phase II enzyme induction, and (c) hepatic pro-inflammatory cytokine gene expression. The results showed that RS-DCM was more potent than RS-H₂O in decreasing GST-P positive foci and apoptotic cells induced by DEN. The mechanisms of RS-DCM (phenolics and sulforaphene contents) against liver carcinogenesis (1) block the activity of carcinogens; (2) elevate phase II detoxifying enzymes; and (3) suppress the pro-inflammatory gene expression. RS-H₂O (phenolics contents), in contrast, only decreases pro-inflammatory gene expression. In conclusion, the RS extract consisting of phenolics and isothiocyanates exerted significant chemopreventive activity against DEN-induced liver carcinogenesis.

Whole grains-derived functional ingredients against hyperglycemia: targeting hepatic glucose metabolism

Type 2 diabetes mellitus (T2DM) is characterized by the dysregulation of glucose homeostasis, resulting in hyperglycemia. However, concerns have been raised about the safety and efficacy of current hypoglycemic drugs due to undesirable side effects. Increasing studies have shown that whole grains (WG) consumption is inversely associated with the risk of T2DM and its subsequent complications. Thus, dietary strategies involving functional components from the WG provide an intriguing approach to restoring and maintaining glucose homeostasis. This review provides a comprehensive understanding of the major functional components derived from WG and their positive effects on glucose homeostasis, demonstrates the underlying molecular mechanisms targeting hepatic glucose metabolism, and discusses the unclear aspects according to the latest viewpoints and current research. Improved glycemic response and insulin resistance were observed after consumption of WG-derived bioactive ingredients, which are involved in the integrated, multi-factorial, multi-targeted regulation of hepatic glucose metabolism. Promotion of glucose uptake, glycolysis, and glycogen synthesis pathways, while inhibition of gluconeogenesis, contributes to amelioration of abnormal hepatic glucose metabolism and insulin resistance by bioactive components. Hence, the development of WG-based functional food ingredients with potent hypoglycemic properties is necessary to manage insulin resistance and T2DM.

Determination of Chemical Composition and Investigation of Biological Activities of Ocimum basilicum L

This study aimed to determine the chemical composition of the essential oils (EOs) of Ocimum basilicum L., as well as to evaluate the antibacterial, antidiabetic, dermatoprotective, and anti-inflammatory properties, and the EOs and aqueous extracts of O. basilicum. The antibacterial activity was evaluated against bacterial strains, Gram-positive and Gram-negative, using the well diffusion and microdilution methods, whereas the antidiabetic activity was assessed in vitro using two enzymes involved in carbohydrate digestion, α-amylase and α-glucosidase. On the other hand, the dermatoprotective and anti-inflammatory activities were studied by testing tyrosinase and lipoxygenase inhibition activity, respectively. The results showed that the chemical composition of O. basilicum EO (OBEO) is dominated by methyl chavicol (86%) and trans-anethol (8%). OBEO exhibited significant antibacterial effects against Gram-negative and Gram-positive strains, demonstrated by considerable diameters of the inhibition zones and lower MIC and MBC values. In addition, OBEO exhibited significant inhibition of α-amylase (IC50 = 50.51 ± 0.32 μg/mL) and α-glucosidase (IC50 = 39.84 ± 1.2 μg/mL). Concerning the anti-inflammatory activity, OBEO significantly inhibited lipoxygenase activity (IC50 = 18.28 ± 0.03 μg/mL) compared to the aqueous extract (IC50 = 24.8 ± 0.01 μg/mL). Moreover, tyrosinase was considerably inhibited by OBEO (IC50 = 68.58 ± 0.03 μg/mL) compared to the aqueous extract (IC50 = 118.37 ± 0.05 μg/mL). The toxicological investigations revealed the safety of O. basilicum in acute and chronic toxicity. The finding of in silico analysis showed that methyl chavicol and trans-anethole (main compounds of OBEO) validate the pharmacokinetics of these compounds and decipher some antibacterial targets.

Identification of Oxidative Stress-Related Biomarkers in Diabetic Kidney Disease

BACKGROUND

Diabetic kidney disease (DKD) is a leading cause of end-stage renal disease throughout the world. In kidney disease, oxidative stress has been linked to both antioxidant depletions and increased reactive oxygen species (ROS) production. Thus, the objective of this study was to identify biomarkers related to oxidative stress in DKD.

METHODS

The gene expression profile of the DKD was extracted from the Gene Expression Omnibus (GEO) database. The identification of the differentially expressed genes (DEGs) was performed using the "limma" R package, and weighted gene coexpression network analysis (WGCNA) was used to find the gene modules that were most related to DKD. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was performed using "Org.Hs.eg.db" R package. The protein-protein interaction (PPI) network was constructed using the STRING database. The hub genes were identified by the Molecular Complex Detection (MCODE) plug-in of Cytoscape software. The diagnostic capacity of hub genes was verified using the receiver operating characteristic (ROC) curve. Correlations between diagnostic genes were analyzed using the "corrplot" package. In addition, the miRNA gene transcription factor (TF) network was used to explain the regulatory mechanism of hub genes in DKD.

RESULTS

DEGs analysis and WGCNA-identified 160 key genes were identified in DKD patients. Among them, nine oxidative stress-related genes were identified as candidate hub genes for DKD. Using the PPI network, five hub genes, NR4A2, DUSP1, FOS, JUN, and PTGS2, were subsequently identified. All the hub genes were downregulated in DKD and had a high diagnostic value of DKD. The regulatory mechanism of hub genes was analyzed from the miRNA gene-TF network.

CONCLUSION

Our study identified NR4A2, DUSP1, FOS, JUN, and PTGS2 as hub genes of DKD. These genes may serve as potential therapeutic targets for DKD patients.

The Nicotinamide/Streptozotocin Rodent Model of Type 2 Diabetes: Renal Pathophysiology and Redox Imbalance Features

Diabetic nephropathy (DN) is a common complication of diabetes mellitus. While there has been a great advance in our understanding of the pathogenesis of DN, no effective managements of this chronic kidney disease are currently available. Therefore, continuing to elucidate the underlying biochemical and molecular mechanisms of DN remains a constant need. In this regard, animal models of diabetes are indispensable tools. This review article highlights a widely used rodent model of non-obese type 2 diabetes induced by nicotinamide (NA) and streptozotocin (STZ). The mechanism underlying diabetes induction by combining the two chemicals involves blunting the toxic effect of STZ by NA so that only a percentage of β cells are destroyed and the remaining viable β cells can still respond to glucose stimulation. This NA-STZ animal model, as a platform for the testing of numerous antidiabetic and renoprotective materials, is also discussed. In comparison with other type 2 diabetic animal models, such as high-fat-diet/STZ models and genetically engineered rodent models, the NA-STZ model is non-obese and is less time-consuming and less expensive to create. Given that this unique model mimics certain pathological features of human DN, this model should continue to find its applications in the field of diabetes research.

Vanillic Acid Attenuates Monocrotaline-Induced Pulmonary Arterial Hypertension by Enhancing NO Signaling Pathways

Pulmonary arterial hypertension (PAH) is a severe progressive disease characterized by elevated mean pulmonary arterial pressure, right ventricular hypertrophy, and eventual progression to right heart failure and death. This study aimed to examine the effect of the natural product vanillic acid (VA) on monocrotaline (MCT)-induced PAH in rats. The arginase inhibitory activity and enzyme kinetic reaction of VA were also investigated. The results showed that VA could improve pulmonary arterial pressure, pulmonary artery vascular remodeling, and right ventricular remodeling induced by MCT in rats and reduce the degree of pulmonary tissue fibrosis. Moreover, VA downregulated the gene and protein expression levels of Hif-2α, Hif-1β, and Arg2 and increased the P-eNOS/eNOS levels, thus increasing nitric oxide (NO) levels in PAH rats. Furthermore, VA was determined to be a mixed competitive arginase inhibitor with an IC50 of 26.1 μM. In conclusion, the arginase inhibitor VA exerted protective effects on MCT-induced PAH and pulmonary vascular remodeling by enhancing NO signaling pathways.

Globularia alypum Extracts Attenuate Hyperglycemia and Protect against Various Organ Toxicities in Alloxan-Induced Experimental Diabetic Rats

In this study, we attempted for the first time to determine the phytochemical compositions and biopharmaceutical properties of Globularia alypum methanol extract (GAME) and Globularia alypum water extract (GAWE). High-performance liquid chromatography with diode array detection (HPLC-DAD) analysis was performed to establish the chemical profile of the investigated extracts. Chemical composition analysis was taken in the presence of various bioactive compounds such as quercetin 7-O-glucoside and apigenin 7-O-glucoside in GAME. In GAWE, various abundant compounds were found in the extract such as quercetin 7-O-glucoside, apigenin, quercetin, apigenin 7-O-glucoside, and cinnamic acid. This study showed that the administration of GAWE and GAME to type 1 diabetic rats decreased fasting blood glucose, protected pancreas β-cells from death and injury, increased liver glycogen rate, and ameliorated oral glucose tolerance test. Moreover, GA reduced weight loss, and diabetes decreased basic physical activity. In addition, the administration of GA extracts in diabetic rats protected from diabetes-induced liver, kidney, testes, heart, and bone toxicities. Conclusion. GAWE has possible value for antidiabetic oral medication.

Rack1 regulates pro-inflammatory cytokines by NF-κB in diabetic nephropathy

Diabetic nephropathy (DN) is one of the chronic microvascular diseases of diabetes. Studies revealed that inflammation is involved in the development of DN. However, its mechanisms are not fully clear. Here, we screened DN-related mRNAs by RNA sequencing in the renal tissues of db/db DN mice and normal control mice. The Swiss-Model, ZDOCK 3.0.2 and PyMOL 2.3.2 were applied for bioinformatics analysis. In total, we obtained 6,820 mRNAs that were dysexpressed in DN. Among them, Receptor for Activated C Kinase 1 (Rack1) was focused on for its high fold changes and high values of fragments per kilobase million (FPKM) in both two groups (FPKM >100). Moreover, Rack1 was highly expressed in DN in vivo and in vitro. Results displayed that the expressions of pro-inflammatory cytokines Mcp-1 and Tnf-α were increased when Rack1 was overexpressed in cells cultured with low glucose while the expressions of Mcp-1 and Tnf-α were decreased when Rack1 was silenced in cells cultured with high glucose. Furthermore, results showed that the established DN inflammatory factor nuclear factor NF-kappa-B (NF-κB) was regulated by Rack1 via the direct interaction between Rack1 and NF-κB subunits P50 and P65. In summary, this identified Rack1 could play an important role in the inflammation of DN via NF-κB, which can provide new insight for DN research.

New Approaches and advancement in drug development from phenolic p-coumaric acid

P-coumaric acid occurs as a common dietary polyphenol distributed in fruits, vegetables, and cereals in associated and free form. The toxicity profile of the drug is very low and it exhibits many pharmacological actions (antihypertensive, anti-inflammatory, anticancer, antimicrobial activity, antidiabetic, anticancer, and antioxidant effect). P-coumaric acid also acts as a free radical scavenger and inhibits various enzymes which generate free radicals. It is also used as the raw material for the preparation of preservatives, vanillin, sports foods, skin defense agents, and as a cross-linker for the formation of edible films and food gels. The current study is based upon biological effectiveness, molecular docking, SAR, sources of p-coumaric acid, and related derivatives.

Mechanisms and Therapeutic Effects of Benzoquinone Ring Analogs in Primary CoQ Deficiencies

Coenzyme Q (CoQ) is a conserved polyprenylated lipid composed of a redox-active benzoquinone ring and a long polyisoprenyl tail that serves as a membrane anchor. CoQ biosynthesis involves multiple steps, including multiple modifications of the precursor ring 4-hydroxybenzoic acid. Mutations in the enzymes involved in CoQ biosynthesis pathway result in primary coenzyme Q deficiencies, mitochondrial disorders whose clinical heterogenicity reflects the multiple biological function of CoQ. Patients with these disorders do not always respond to CoQ supplementation, and CoQ analogs have not been successful as alternative approaches. Progress made in understanding the CoQ biosynthesis pathway and studies of supplementation with 4-hydroxybenzoic acid ring analogs have opened a new area in the field of primary CoQ deficiencies treatment. Here, we will review these studies, focusing on efficacy of the different 4-hydroxybenzoic acid ring analogs, models in which they have been tested, and their mechanisms of action. Understanding how these compounds ameliorate biochemical, molecular, and/or clinical phenotypes of CoQ deficiencies is important to develop the most rational treatment for CoQ deficient patients, depending on their molecular defects.