Crocin mediated amelioration of oxidative burden and inflammatory cascade suppresses diabetic nephropathy progression in diabetic rats

Alogliptin attenuates STZ-induced diabetic nephropathy in rats through the modulation of autophagy, apoptosis, and inflammation pathways: Targeting NF-κB and AMPK/mTOR pathway

AIM

Diabetic nephropathy (DN) is a type of microvascular complication that arises from diabetes mellitus and leads to further health issues. Most importantly, the prevalence of DN is steadily rising in developed countries. This research explored the therapeutic benefits of alogliptin, a dipeptidyl peptidase IV (DPP-4) inhibitor, on streptozotocin (STZ)-induced DN and its underlying mechanisms in rats.

MAIN METHODS

Ten rats were allocated to group 1, served as the normal group; and received saline. To develop diabetes, thirty rats were administered a single intraperitoneal dose of STZ (45 mg/kg). STZ-induced diabetic rats were randomly assigned to three groups: group 2 diabetic control; was given saline, groups 3 and 4 received alogliptin (10 mg/kg) and (20 mg/kg), respectively. The treatment began 8 weeks after diabetes onset and continued for four weeks. Histopathological alterations in the kidney were detected. Serum was collected to measure blood glucose levels (BGL), renal function, and lactate dehydrogenase (LDH). Tissue samples were collected to detect changes in oxidative stress (OS), inflammation, 5' adenosine monophosphate-activated protein kinase (AMPK), and the mammalian target of Rapamycin (mTOR) signaling pathways in addition to apoptotic and autophagy changes.

KEY FINDINGS

Alogliptin reduced STZ-induced histological changes in the kidney as well as OS, and inflammation. Alogliptin also ameliorated the AMPK/mTOR signaling pathways, enhanced autophagy, and reduced apoptosis.

SIGNIFICANCE

These results demonstrate that alogliptin ameliorates inflammation and OS and consequently modulates the AMPK/mTOR axis along with targeting autophagy and apoptosis, leading to the alleviation of DN.

Potential therapeutic effects of crocin

Crocin, a natural bioactive compound derived from saffron (Crocus sativus) and other Crocus genera, has gained significant attention recently due to its potential therapeutic properties. The multifaceted nature of crocin's biological effects has piqued the interest of researchers and health enthusiasts, prompting further investigations into its mechanisms of action and therapeutic applications. This review article comprehensively explores the emerging evidence supporting crocin's role as a promising ally in protecting against metabolic disorders. The review covers the molecular mechanisms underlying crocin's beneficial effects and highlights its potential applications in preventing and treating diverse pathological conditions. Understanding the mechanisms through which crocin exerts its protective effects could advance scientific knowledge and offer potential avenues for developing novel therapeutic interventions. As we uncover the potential of crocin as a valuable ally in the fight against disorders, it becomes evident that nature's palette holds remarkable solutions for enhancing our health.

Association between oxidative balance score and diabetic kidney disease, low estimated glomerular filtration rate and albuminuria in type 2 diabetes mellitus patients: a cross-sectional study

Objective

The oxidative balance score (OBS) is a comprehensive concept that includes 20 oxidative stressors and can be used to assess individual pro-oxidant versus antioxidant exposure, and the aim of the present study was to investigate the association between OBS and the risk of diabetic kidney disease (DKD), low estimated glomerular filtration rate (low-eGFR) and albuminuria in patients with diabetes mellitus (DM).

Methods

This cross-sectional study included nationally representative consecutive National Health and Nutrition Examination Survey DM patients aged 18 years and older from 2003-2018. The continuous variable OBS was converted into categorical variables by quartiles, and weighted multiple logistic regression analyses and restricted triple spline models were used to explore the relationships. We also performed subgroup analyses and interaction tests to verify the stability of the results.

Results

A total of 5389 participants were included, representing 23.6 million non-institutionalized US residents. The results from both multivariate logistic regression analysis and restricted cubic spline models indicated that OBS and dietary OBS levels were negatively associated with the risk of DKD, low-eGFR, and albuminuria, without finding a significant correlation between lifestyle OBS and these clinical outcomes. Compared to the lowest OBS quartile group, the prevalence risk of DKD (OR = 0.61, 95% CI: 0.46-0.80), low-eGFR (OR = 0.46, 95% CI: 0.33-0.64) and albuminuria (OR = 0.68, 95% CI: 0.51-0.92) decreased by 39%, 54% and 32%, respectively, in the highest OBS quartile group. The results remained stable in subgroup analyses and no interaction between subgroups was found.

Conclusion

Higher levels of OBS and dietary OBS were associated with a lower risk of DKD, low-eGFR, and albuminuria. These findings provided preliminary evidence for the importance of adhering to an antioxidant-rich diet and lifestyle among individuals with diabetes.

Renoprotective effect of a novel combination of 6-gingerol and metformin in high-fat diet/streptozotocin-induced diabetic nephropathy in rats via targeting miRNA-146a, miRNA-223, TLR4/TRAF6/NLRP3 inflammasome pathway and HIF-1α

BACKGROUND

MiRNA-146a and miRNA-223 are key epigenetic regulators of toll-like receptor 4 (TLR4)/tumor necrosis factor-receptor-associated factor 6 (TRAF6)/NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome pathway, which is involved in diabetic nephropathy (DN) pathogenesis. The currently available oral anti-diabetic treatments have been insufficient to halt DN development and progression. Therefore, this work aimed to assess the renoprotective effect of the natural compound 6-gingerol (GR) either alone or in combination with metformin (MET) in high-fat diet/streptozotocin-induced DN in rats. The proposed molecular mechanisms were also investigated.

METHODS

Oral gavage of 6-gingerol (100 mg/kg) and metformin (300 mg/kg) were administered to rats daily for eight weeks. MiRNA-146a, miRNA-223, TLR4, TRAF6, nuclear factor-kappa B (NF-κB) (p65), NLRP3, caspase-1, and hypoxia-inducible factor-1 alpha (HIF-1α) mRNA expressions were measured using real-time PCR. ELISA was used to measure TLR4, TRAF6, NLRP3, caspase-1, tumor necrosis factor-alpha (TNF-α), and interleukin-1-beta (IL-1β) renal tissue levels. Renal tissue histopathology and immunohistochemical examination of fibronectin and NF-κB (p65) were performed.

RESULTS

6-Gingerol treatment significantly reduced kidney tissue damage and fibrosis. 6-Gingerol up-regulated miRNA-146a and miRNA-223 and reduced TLR4, TRAF6, NF-κB (p65), NLRP3, caspase-1, TNF-α, IL-1β, HIF-1α and fibronectin renal expressions. 6-Gingerol improved lipid profile and renal functions, attenuated renal hypertrophy, increased reduced glutathione, and decreased blood glucose and malondialdehyde levels. 6-Gingerol and metformin combination showed superior renoprotective effects than either alone.

CONCLUSION

6-Gingerol demonstrated a key protective role in DN by induction of miRNA-146a and miRNA-223 expression and inhibition of TLR4/TRAF6/NLRP3 inflammasome signaling. 6-Gingerol, a safe, affordable, and abundant natural compound, holds promise for use as an adjuvant therapy with metformin in diabetic patients to attenuate renal damage and stop the progression of DN.

Exploring the NRF2/HO-1 and NF-κB Pathways: Spirulina Nanoparticles as a Novel Approach to Combat Diabetic Nephropathy

Arthrospira platensis has been the subject of plentiful studies due to its purported health advantages; nevertheless, additional investigation is required to determine whether several chronic diseases may be treated or avoided with its nanoform. Therefore, we set out to examine A. platensis nanoparticles (SNPs) to protect against kidney impairment caused by Streptozotocin (STZ) in diabetic rats, precisely focusing on its effect and the cellular intracellular pathways involved. Male Wistar rats were assigned into four groups: Group 1 was set as control, comprising the normal rats; group 2 was administered SNPs (0.5 mg/kg BW, once/day) orally for 84 consecutive days; group 3, STZ-diabetic rats were injected with STZ (65 mg/kg BW); and group 4, in which the diabetic rats were treated with SNPs. After inducing diabetes in rats for 84 days, the animals were euthanized. The results disclosed that SNP treatment substantially (P < 0.05) improved the glucose and glycated hemoglobin levels (HbA1c %), insulin, C-peptide, and cystatin C deterioration in diabetic rats. Furthermore, SNP administration significantly lowered (P < 0.05) nitric oxide (NO) and malondialdehyde (MDA) levels in renal tissue and enhanced kidney function metrics, as well as improved the antioxidant capacity of the renal tissue. In addition, oral SNPs overcame the diabetic complications concerning diabetic nephropathy, indicated by downregulation and upregulation of apoptotic and antiapoptotic genes, respectively, along with prominent modulation of the antiangiogenic marker countenance level, improving kidney function. SNP modulated the nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 (NRF2/HO-1) pathways and inhibited the nuclear factor-κB (NF-κB) expression, strengthening the SNP pathways in alleviating diabetic nephropathy. The histopathology results corroborated the obtained biochemical and molecular observations, suggesting the therapeutic potential of SNPs in diabetic nephropathy via mechanisms other than its significant antioxidant and hypoglycemic effects, including modulation of antiangiogenic and inflammatory mediators and the NRF2/HO-1 pathways.

Non-coding RNA transcripts, incredible modulators of cisplatin chemo-resistance in bladder cancer through operating a broad spectrum of cellular processes and signaling mechanism

Bladder cancer (BC) is a highly frequent neoplasm in correlation with significant rate of morbidity, mortality, and cost. The onset of BC is predominantly triggered by environmental and/or occupational exposures to carcinogens, such as tobacco. There are two distinct pathways by which BC can be developed, including non-muscle-invasive papillary tumors (NMIBC) and non-papillary (or solid) muscle-invasive tumors (MIBC). The Cancer Genome Atlas project has further recognized key genetic drivers of MIBC along with its subtypes with particular properties and therapeutic responses; nonetheless, NMIBC is the predominant BC presentation among the suffering individuals. Radical cystoprostatectomy, radiotherapy, and chemotherapy have been verified to be the common therapeutic interventions in metastatic tumors, among which chemotherapeutics are more conventionally utilized. Although multiple chemo drugs have been broadly administered for BC treatment, cisplatin is reportedly the most effective chemo drug against the corresponding malignancy. Notwithstanding, tumor recurrence is usually occurred following the consumption of cisplatin regimens, particularly due to the progression of chemo-resistant trait. In this framework, non-coding RNAs (ncRNAs), as abundant RNA transcripts arise from the human genome, are introduced to serve as crucial contributors to tumor expansion and cisplatin chemo-resistance in bladder neoplasm. In the current review, we first investigated the best-known ncRNAs, i.e. microRNAs (miRNAs), long ncRNAs (lncRNAs), and circular RNAs (circRNAs), correlated with cisplatin chemo-resistance in BC cells and tissues. We noticed that these ncRNAs could mediate the BC-related cisplatin-resistant phenotype through diverse cellular processes and signaling mechanisms, reviewed here. Eventually, diagnostic and prognostic potential of ncRNAs, as well as their therapeutic capabilities were highlighted in regard to BC management.

Use of Transcriptome Sequencing to Analyze the Effects of Different Doses of an Astragalus-Rhubarb-Saffron Mixture in Mice with Diabetic Kidney Disease

Purpose

To investigate the therapeutic effect and underlying mechanism of a traditional Chinese medicine (TCM) mixture consisting of Astragalus, rhubarb, and saffron in a mouse model of diabetic kidney disease (DKD).

Methods

Forty-eight db/db mice received no TCM (DKD model), low-dose TCM, medium-dose TCM, or high-dose TCM, and an additional 12 db/m mice received no TCM (normal control). Intragastric TCM or saline (controls) was administered daily for 24 weeks. Blood glucose, body weight, serum creatinine (SCr), blood urea nitrogen (BUN), blood lipids, and urinary microalbumin were measured every four weeks, and the urinary albumin excretion rate (UAER) was calculated. After 24 weeks, kidney tissues were collected for transcriptome sequencing, and the main functions of these genes were determined via functional enrichment analysis.

Results

Compared with the DKD model group, the medium-dose and high-dose TCM groups had significantly decreased levels of SCr, BUN, total cholesterol, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and UAER (all p<0.05). We identified 42 genes that potentially functioned in this therapeutic response, and the greatest effect on gene expression was in the high-dose TCM group. We also performed functional enrichment analysis to explore the potential mechanisms of action of these different genes.

Conclusion

A high-dose of the Astragalus-rhubarb-saffron TCM provided the best prevention of DKD. Analysis of the kidney transcriptome suggested that this TCM mixture may prevent DKD by altering immune responses and oxygen delivery by hemoglobin.

The anti-inflammatory effect of metformin: The molecular targets

Metformin is an anti-diabetic drug. Metformin mainly inhibits gluconeogenesis in the liver and reduces blood sugar. In addition to the anti-diabetic effects, many studies have revealed that metformin has anti-inflammatory effects. Various molecules were suggested to be the target of the metformin's anti-inflammatory effects. However, the conclusion is not clear. Metformin is related to a number of molecules and the identification of the main target in anti-inflammatory effects leads to the understanding of inflammation and metformin. In this article, I discuss each suggested molecule, involved mechanisms, and their relationship with various diseases.

Effect of Crocus sativus L. (saffron) and crocin in the treatment of patients with type-2 diabetes mellitus: A systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Crocus sativus L. (saffron, Iridaceae) has been traditionally used for thousands of years as herbal medicine for many diseases, including type-2 diabetes mellitus (T2DM), especially in Sri Lanka. Systematic reviews and meta-analysis on C. sativus for T2DM value traditional knowledge about this species.

AIM OF THE STUDY

To assess the effectiveness of C. sativus powdered plant, hydroethanolic extract and crocin in reducing fasting blood sugar (FBG), glycated hemoglobin (HbA1c), blood pressure, and other metabolic parameters in patients with T2DM.

MATERIAL AND METHODS

Systematic review and meta-analysis based on searches in PubMed, Embase, and Cochrane, including all randomized clinical trials (RCTs) published before January 2, 2023. Two independent reviewers extracted the data and assessed the risks of bias. The effects of C. sativus and crocin were assessed on glycemic, metabolic, and blood pressure parameters. Weighted (WMD) or standardized (SMD) mean differences (before-after) and 95% confidence intervals (95%CI) of the outcomes were extracted or estimated and meta-analyses were conducted using RevMan 5.4 (Cochrane Collaboration). This protocol was registered in PROSPERO (#CRD42023390073).

RESULTS

Fifteen of 29 studies were included. Saffron powdered plant decreased AST (WMD -1.19, 95%CI -2.24, -0.13), but increased BMI (WMD 0.56, 95%CI 0.07, 1.05); saffron extract decreased HbA1c (WMD -0.35, 95%CI -0.65, -0.06), FBG (WMD -26.90, 95%CI -38.87, -14.93), creatinine (WMD -0.12, 95%CI -0.19, -0.05), and total cholesterol (WMD -9.29, 95%CI -18.25, -0.33); and crocin decreased HbA1c (WMD -0.43, 95%CI -0.66, -0.20), FBG (WMD -14.10, 95%CI -22.91, -5.30), and systolic blood pressure (WMD -8.18, 95%CI -12.75, -3.61), but increased creatinine levels (WMD 0.24, 95%CI 0.17, 0.32). Of the 15 included studies, 14 had a moderate risk of bias, and one study had a low risk of bias.

CONCLUSION

C. sativus (saffron) powdered plant, extract, and crocin have potential as an adjunct treatment for T2DM, improving control of metabolic and clinical parameters. However, C. sativus extract seems to be superior because it was effective in more parameters and did not induce adverse effects. Since many studies were at moderate risk of bias, further high-quality research is needed to firmly establish the clinical efficacy of this plant.

Effect of crocin and treadmill exercise on oxidative stress and heart damage in diabetic rats

Diabetes increases the production of free radicals and inflammatory agents in the heart tissue and alters the expression of genes associated with the induction of apoptosis. Considering the importance of common cardiovascular disorders in diabetes, this study investigated the effect of eight weeks of aerobic exercise and crocin use, as well as tissue damage and oxidative stress caused by diabetes in the hearts of adult rats. Streptozotocin 50 mg/kg was injected as a single dose intraperitoneally to cause the diabetes. After 72 hours, a glucometer monitored blood glucose levels, and blood glucose above 250 mg/dl was considered diabetes. Continuous treadmill exercise was performed for eight weeks by placing the animal on the treadmill. Next, the animals were anesthetized, and samples were taken from the hearts and frozen in liquid nitrogen. Then, superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde (MDA) were measured in the cardiac tissue. Finally, the hearts of half of the animals were immediately immersed in a formalin solution for histological changes. According to our findings, diabetes increased lipid peroxidation, characterized by increased MDA levels in the control diabetes group and decreased SOD and GPx levels (P <0.05). It also changes the balance of expression of genes associated with apoptosis control, increased Bcl-2-associated X (Bax) expression, and decreased Bcl-2 expression (P <0.05). Also, we observed the induction of apoptosis in cardiac tissue. Using eight weeks of continuous exercise and administration of crocin significantly reduced blood sugar levels and lipid peroxidation and increased the activity of antioxidant enzymes and Bcl-2 gene expression compared to the diabetes control group. In addition, continuous exercise and crocin improved the oxidative stress parameters in the control group. This study showed that diabetes could cause oxidative stress and heart dysfunction. Moreover, simultaneously and separately, aerobic exercise with a treadmill and crocin administration can reduce these disorders and prevent apoptosis in the heart tissue.

Gardenia (Gardenia jasminoides Ellis) fruit: a critical review of its functional nutrients, processing methods, health-promoting effects, comprehensive application and future tendencies

Gardenia fruit (GF) is the mature fruit of Gardenia jasminoides Ellis, boasting a rich array of nutrients and phytochemicals. Over time, GF has been extensively utilized in both food and medicinal contexts. In recent years, numerous studies have delved into the chemical constituents of GF and their associated pharmacological activities, encompassing its phytochemical composition and health-promoting properties. This review aims to provide a critical and comprehensive summary of GF research, covering nutrient content, extraction technologies, and potential health benefits, offering new avenues for future investigations and highlighting its potential as an innovative food resource. Additionally, the review proposes novel industrial applications for GF, such as utilizing gardenia yellow/red/blue pigments in the food industry and incorporating it with other herbs in traditional Chinese medicine. By addressing current challenges in developing GF-related products, this work provides insights for potential applications in the cosmetics, food, and health products industries. Notably, there is a need for the development of more efficient extraction methods to harness the nutritional components of GF fully. Further research is needed to understand the specific molecular mechanisms underlying its bioactivities. Exploring advanced processing techniques to create innovative GF-derived products will show great promise for the future.

Crocin improves the renal autophagy in rat experimental membranous nephropathy via regulating the SIRT1/Nrf2/HO-1 signaling pathway

Membranous nephropathy (MN) is a glomerular disease. Crocin is isolated from saffron and gardenia. Its antioxidant, anti-inflammatory, anti-hyperlipidemic, anti-atherosclerotic, anti-tumor, free-radical scavenging and neuroprotective activities have been well established. We investigated the biological functions of crocin and its related mechanisms in MN. We established an experimental passive Heymann nephritis (PHN) rat model induced by anti-Fx1A antiserum. The rats were divided into sham, sham + crocin, PHN, PHN + crocin, and PHN + enalapril groups. Blood samples and kidneys of rats were collected for estimation of biochemical parameters in serum and oxidative stress indicators in kidney tissues. Histopathological changes of renal tissues were evaluated by hematoxylin and eosin, periodic acid-Schiff (PAS) and Masson staining. The podocyte number was estimated by immunohistochemistry staining of Wilms tumor type 1 (WT1). The deposition of rat anti-rabbit IgG antibodies, complement C3 and C5b-9 was detected by immunofluorescence staining. Western blotting was performed to measure the levels of Sirtuin 1 (Sirt1), nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1) and apoptosis-related proteins. The total cholesterol, triglycerides, creatinine, blood urea nitrogen, urine volume and urine albumin of PMN rats were significantly reduced by crocin. Additionally, crocin attenuated the renal histopathological changes. Moreover, the oxidative stress damage and podocyte loss and immune injury were relieved by crocin in PHN rats. Mechanistically, crocin administration activated the Sirt1/Nrf2/HO-1 pathways. The results provide a scientific basis that crocin could alleviate MN by inhibiting immune injury and podocyte damage through activating the Sirt1/Nrf2/HO-1 pathways.

Advances in the pharmacological study of Chinese herbal medicine to alleviate diabetic nephropathy by improving mitochondrial oxidative stress

Diabetic nephropathy (DN) is one of the serious complications of diabetes mellitus, primarily arising from type 2 diabetes (T2DM), and can progress to chronic kidney disease (CKD) and end stage renal disease (ESRD). The pathogenesis of DN involves various factors such as hemodynamic changes, oxidative stress, inflammatory response, and lipid metabolism disorders. Increasing attention is being given to DN caused by oxidative stress in the mitochondrial pathway, prompting researchers to explore drugs that can regulate these target pathways. Chinese herbal medicine, known for its accessibility, rich historical usage, and remarkable efficacy, has shown promise in ameliorating renal injury caused by DN by modulating oxidative stress in the mitochondrial pathway. This review aims to provide a reference for the prevention and treatment of DN. Firstly, we outline the mechanisms by which mitochondrial dysfunction impairs DN, focusing on outlining the damage to mitochondria by oxidative stress. Subsequently, we describe the process by which formulas, herbs and monomeric compounds protect the kidney by ameliorating oxidative stress in the mitochondrial pathway. Finally, the rich variety of Chinese herbal medicine, combined with modern extraction techniques, has great potential, and as we gradually understand the pathogenesis of DN and research techniques are constantly updated, there will be more and more promising therapeutic targets and herbal drug candidates. This paper aims to provide a reference for the prevention and treatment of DN.

A review of therapeutic impacts of saffron (Crocus sativus L.) and its constituents

Application of herbal medicines in the treatment of diseases is in the center of attention of medical scientific societies. Saffron (Cricus sativus L.) is a medicinal plant belonging to the Iridaceae family with different therapeutic properties. The outcomes of human and animal experiments indicate that therapeutic impacts of saffron and its constituents, crocin, crocetin, and safranal, mainly are mediated via inhibiting the inflammatory reactions and scavenging free radicals. It has been suggested that saffron and crocin extracted from it also up-regulate the expression of sirtuin 1 (SIRT1) and nuclear factor erythroid 2-related factor 2 (Nrf2), down-regulate nuclear factor kappa B (NF-κB) signaling pathway and untimely improve the body organs dysfunction. Inhibition of inducible nitric oxide synthase and cyclooxygenase-2 (COX2) also is attributed to crocin. The current review narrates the therapeutic effects of saffron and its constituents on various body systems through looking for the scientific databases including Web of Science, PubMed, Scopus, and Google Scholar from the beginning of 2010 until the end of 2022.

Comparison of the effect of saffron, crocin, and safranal on serum levels of oxidants and antioxidants in diabetic rats: A systematic review and meta-analysis of animal studies

This study aimed to evaluate the effect of saffron, crocin, and safranal on serum levels of oxidants and antioxidants in diabetic rats. The authors searched the databases with standard keywords until June 8, 2021. The random-effects model was used to pool standardized mean differences (SMD) with 95% confidence intervals to assess the effects of saffron and its active component. To investigate heterogeneity, subgroup analysis and meta-regression were utilized. Begg and Egger's tests were used to measure publication bias. Our results showed that saffron, crocin, and safranal were able to significantly reduce the serum levels of oxidants with strong efficacy so that saffron had the highest effectiveness on serum malondialdehyde (SMD, -2.84 (μmol/L) [95% confidence interval (CI), -4.32 to -1.36]; p < .001, I 2 = 83.5%). In addition, saffron and its effective compounds were highly effective by increasing the serum level of antioxidants. In addition, saffron and its effective compounds were able to significantly increase the serum level of antioxidants with strong efficacy, while saffron had the highest effect on the serum level of total antioxidant capacity (SMD, 3.90 (μmol/L) [95% CI, 0.78-7.03]; p = .014, I 2 = 86.9%). The findings of this study show that treatment with saffron, crocin, and safranal by strengthening the antioxidant defense system and modulating oxidative stress shows antidiabetic effects in the diabetic model of rats, also these findings support the potential effect of saffron and its effective compounds for the management of diabetes and its complications. However, more human studies are needed.

Effective Therapeutic Verification of Crocin I, Geniposide, and Gardenia (Gardenia jasminoides Ellis) on Type 2 Diabetes Mellitus In Vivo and In Vitro

For many centuries, Gardenia (Gardenia jasminoides Ellis) was highly valued as a food homologous Chinese herbal medicine with various bioactive compounds, including crocin I and geniposide. However, the functional mechanism underlying the hypoglycemic effect of gardenia is absent in the literature. To evaluate the effect of gardenia and its different extracts on type 2 diabetes mellitus (T2DM) in in vivo and in vitro experiments, the dried gardenia powder was extracted using 60% ethanol and eluted at different ethanol concentrations to obtain the corresponding purified fragments. After that, the active chemical compositions of the different purified gardenia fragments were analyzed using HPLC. Then, the hypoglycemic effects of the different purified gardenia fragments were compared using in vitro and in vivo experiments. Finally, the different extracts were characterized using UPLC-ESI-QTOF-MS/MS and the mass spectrometric fragmentation pathway of the two main compounds, geniposide and crocin I, were identified. The experimental results indicated that the inhibitory effect of the 40% EGJ (crocin I) on the α-glucosidase was better than the 20% EGJ (geniposide) in vitro. However, the inhibitory effect of geniposide on T2DM was better than crocin I in the animal experiments. The different results in vivo and in vitro presumed potentially different mechanisms between crocin I and geniposide on T2DM. This research demonstrated that the mechanism of hypoglycemia in vivo from geniposide is not only one target of the α-glucosidase but provides the experimental background for crocin I and the geniposide deep processing and utilization.

Moringa oleifera impedes protein glycation and exerts reno-protective effects in streptozotocin-induced diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Moringa oleifera is a valued plant with wide distribution in tropical and subtropical regions of the world. It is traditionally used for the treatment of fever, infections, rheumatism, cancer, improving cardiac, renal and hepatic functions, and regulating blood glucose level. The plant has been scientifically reported for the anti-inflammatory, antioxidant, renoprotective, and anti-diabetic properties. Diabetic patients are prone to develop end-stage renal diseases due to incidence of diabetes-induced renal dysfunctions. Given that, increased production and accumulation of advanced glycation end-products (AGEs) play a conspicuous role in the development of diabetes-linked renal dysfunctions, nature-based interventions with AGEs inhibitory activity can prevent renal dysfunctions leading to renoprotection.

AIM OF THE STUDY

The study aimed to demonstrate the preventive effects of the ethanolic extract of the leaves of Moringa oleifera (EEMO) on protein glycation and its further assessment for the renoprotective effect in diabetic rats.

MATERIALS AND METHODS

Antiglycation activity of EEMO was assessed in vitro using bovine serum albumin. For reno-protective activity assessment, streptozotocin (STZ)-induced diabetic rats were orally treated with EEMO (100 mg/kg) or standard antiglycation agent aminoguanidine (100 mg/kg) for consecutive 8 weeks. The effects on glucose homeostasis, renal functions, and renal morphology were assessed by clinical biochemistry, molecular and histological examination.

RESULTS

Presence of EEMO efficiently prevented glucose-, fructose- or methylglyoxal-mediated glycation of protein. Under in vivo set-up, compared to diabetic control rats, EEMO treatment effectively improved the glucose tolerance and body weight, and reduced the serum levels of triglycerides and total cholesterol. Additionally, EEMO administration significantly ameliorated renal dysfunctions in diabetic rats characterized by improved levels of creatinine, urea nitrogen, and uric acid in serum, and total protein level in urine, accompanied by improved kidney morphology. The diabetes-associated pro-inflammatory response characterized by upregulated expression of the inducible nitric oxide synthase (iNos), activation of nuclear factor kappa B (NF-κB) and the raised levels of inflammatory factors, interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) in renal tissue was significantly attenuated in EEMO-treated rats. Moreover, EEMO treatment diminished renal reactive oxygen species (ROS) levels in diabetic animals.

CONCLUSIONS

Our study demonstrated that EEMO prevented AGEs formation and ameliorated renal dysfunctions in diabetic rats by blocking inflammatory/oxidative pathways. Our observations justify M. oleifera as a potential source of therapeutic interventions for diabetic nephropathy management.

Effect of crocin and losartan on biochemical parameters and genes expression of FRMD3 and BMP7 in diabetic rats

BACKGROUND

Diabetes is a multifactorial and growing disease, one of the severe complications of which is diabetic nephropathy (DN), which is the most common cause of chronic renal failure. FERM domain containing 3 (FRMD3) is responsible for maintaining the shape and integrity of nephron cells, and bone morphogenetic protein 7 (BMP7) helps maintain function and reduce kidney damage. This study aimed to evaluate the effect of crocin and losartan on biochemical parameters and the expression of FRMD3 and BMP7 genes in streptozotocin (STZ)-induced diabetic rats.

METHODS

Forty male Wistar rats were randomly divided into five experimental groups as healthy, diabetic control (D), crocin, losartan, and diabetic rats treated with losartan-crocin (n = 8). A single dose of STZ (50 mg/kg intraperitoneally injection) was used to induce diabetes. Four weeks after induction of diabetes, rats received crocin (50 mg/kg) and losartan (25 mg/kg) daily for four weeks orally. Rats were sacrificed at the end of the intervention, and blood samples were taken to determine serum levels of glucose, urea, creatinine (Cr), malondialdehyde (MDA), and thiol. Real-time polymerase chain reaction (PCR) was used to assess the expression of the FRMD3 and BMP7 genes in the kidney samples.

RESULTS

Diabetes induction increased serum levels of glucose, Cr, urea, MDA, and thiol, but decreased BMP7 and FRMD3 genes expression. Treatment with crocin and losartan decreased these biochemical parameters and increased the expression of the BMP7 and FRMD3 genes.

DISCUSSION

Crocin may be a promising therapeutic agent for preventing and improving diabetes-related kidney disease due to its antidiabetic and antioxidant properties.

Saffron as a promising therapy for diabetes and Alzheimer's disease: mechanistic insights

The prevalence of both Alzheimer's disease (AD) and diabetes mellitus is increasing with the societies' aging and has become an essential social concern worldwide. Accumulation of amyloid plaques and neurofibrillary tangles (NFTs) of tau proteins in the brain are hallmarks of AD. Diabetes is an underlying risk factor for AD. Insulin resistance has been proposed to be involved in amyloid-beta (Aβ) aggregation in the brain. It seems that diabetic conditions can result in AD pathology by setting off a cascade of processes, including inflammation, mitochondrial dysfunction, and ROS and advanced glycation end products (AGEs) synthesis. Due to the several side effects of chemical drugs and their high cost, using herbal medicine has recently attracted attention for the treatment of diabetes and AD. Saffron and its active ingredients have been used for its anti-inflammatory, anti-oxidant, anti-diabetic, and anti-AD properties. Therefore, in the present review paper, we take account of the clinical, in vivo and in vitro evidence regarding the anti-diabetic and anti-AD effects of saffron and discuss the preventive or postponing properties of saffron or its components on AD development via its anti-diabetic effects.

Evaluation of therapeutic effects of crocin in attenuating the progression of diabetic nephropathy: a preliminary randomized triple-blind placebo-controlled trial

Background

Diabetic nephropathy (DN) is one of the most important complications of type 2 diabetes (T2DM). Oxidative stress and inflammatory cytokines play an essential role in the development and progression of DN. Despite adopting appropriate therapies, many patients with DN progress to end-stage renal disease (ESRD). Therefore, exploring innovative strategies for better management of DN is crucial. Crocin, a natural compound found in saffron, has profound antioxidant, antifibrotic and anti-inflammatory properties. This study aimed to evaluate the therapeutic effects of crocin in attenuation of the progression of DN.

Methods

In this randomized, triple-blind, placebo-controlled clinical trial, 44 patients with T2DM and microalbuminuria were randomly assigned to receive either crocin (15 mg/day) or a placebo for 90 days. Eventually, 40 patients completed the study: 21 patients in the crocin group and 19 in the placebo group. The primary outcome was a change in urine Albumin-to-Creatinine Ratio (uACR) from baseline to the end of the treatment period. We also evaluated metabolic, anthropometric, and biochemical parameters as the secondary outcomes.

Results

The results of the present study showed that uACR increased in both groups, but the increment was not significantly higher in the crocin group compared with the placebo. Serum levels of transforming growth factor-β (TGF-β) decreased in the crocin group and increased in the placebo group, but none of these changes was significant. Crocin significantly reduced triglyceride (TG) as an important metabolic parameter (P-Value = 0.03).

Conclusion

This study has shown that crocin may be a safe and potential adjunct to conventional therapies for DN patients but because of our limitations such as short duration of the treatment period, and prescribing low doses of crocin, we could not achieve the significant level.

The effects of saffron supplementation on the measures of renal function indicators: a systematic review and meta-analysis

CONTEXT

Saffron (Crocus sativus L.) has been proposed as a potential agent to improve renal function in animal studies. But, due to insufficient evidence in human research, further investigation is needed.

OBJECTIVE

To fill this knowledge gap, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of saffron supplementation on the measures of renal function indicators in adults. Renal function was assessed based on serum urea, blood urea nitrogen, and creatinine levels.

METHOD AND MATERIALS

A systematic search in PubMed/Medline, Scopus, Web of Science, Embase, and Google Scholar databases was done until March 2021 using relevant keywords. A random-effects model was used to estimate the weighted mean difference (WMD) and 95% confidence (95% CI). Nine RCTs were included in the meta-analysis, and their quality was assessed using the Cochrane risk of bias tool.

RESULTS

The pooled analysis showed that saffron supplementation had no significant effect on serum urea concentrations (WMD: - 1.05 mg/dl; 95% CI - 5.1 to 3; P = 0.6, I2 = 93%, P < 0.001) and serum creatinine levels (WMD: - 0.006 mg/dl; 95% CI - 0.08 to 0.06; P = 0.8, I2 = 79%, P < 0.001) when compared to the placebo group. In the dose-response analysis, we observed a significant non-linear relationship between the duration of saffron supplementation and serum urea and creatinine levels.

CONCLUSIONS

Based on our findings, Saffron supplementation had no significant effect on renal function markers, including urea and creatinine. However, further trials are required to determine the actual effect and safety of saffron intervention in human studies.

PROSPERO SUBMISSION ID

248081.

Crocin molecular signaling pathways at a glance: A comprehensive review

Crocin is a hydrophilic carotenoid that is synthesized in the flowers of the Crocus genus. Numerous in vitro and in vivo research projects have been published about the biological and pharmacological properties and toxicity of crocin. Crocin acts as a memory enhancer, anxiolytic, aphrodisiac, antidepressant, neuroprotective, and so on. Here, we introduce an updated and comprehensive review of crocin molecular mechanisms based on previously examined and mentioned in the literature. Different studies confirmed the significant effect of crocin to control pathological conditions, including oxidative stress, inflammation, metabolic disorders, neurodegenerative disorders, and cancer. The neuroprotective effect of crocin could be related to the activation of phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT)/mammalian target of rapamycin (mTOR), Notch, and cyclic-AMP response element-binding protein signaling pathways. The crocin also protects the cardiovascular system through the inhibitory effect on toll-like receptors. The regulatory effect of crocin on PI3K/AKT/mTOR, AMP-activated protein kinase, mitogen-activated protein kinases (MAPK), and peroxisome proliferator-activated receptor pathways can play an effective role in the treatment of metabolic disorders. The crocin has anticancer activity through the PI3K/AKT/mTOR, MAPK, vascular endothelial growth factor, Wnt/β-catenin, and Janus kinases-signal transducer and activator of transcription suppression. Also, the nuclear factor-erythroid factor 2-related factor 2 and p53 signaling pathway activation may be effective in the anticancer effect of crocin. Finally, among signaling pathways regulated by crocin, the most important ones seem to be those related to the regulatory effect on the PI3K/AKT/mTOR pathway.

p-Coumaric acid attenuates high-fat diet-induced oxidative stress and nephropathy in diabetic rats

The prevalence of persistent hyperglycaemia during diabetes, impair antioxidant defence system and generate reactive oxygen species, which majorly contribute to its progression and associated complications. Phytochemicals were suggested to scavenge-free radicals and exert antioxidant effects required to improve insulin sensitivity and reduce the occurrence of diabetes-associated complications. We hypothesise that a phenolic phytochemical p-coumaric can reduce diabetes-induced oxidative stress and improve diabetes-associated nephropathy in rats. The aim of this study is to analyse the protective effects of p-coumaric acid against diabetes-induced oxidative stress and nephropathy in high-fat diet-induced diabetic rats. The oral feeding of p-coumaric acid (20 mg/kg for 12 weeks) was found to significantly decrease the elevated levels of blood glucose in high-fat diet-induced type 2 diabetic rats. p-Coumaric acid treatment also decreases the kidney weight whilst increasing the total body weight of diabetic rats. Furthermore whilst evaluation of the different renal functioning tests, p-coumaric acid significantly improves histopathological changes and the levels of urea, creatinine and uric acid in serum of diabetic rats, which was otherwise elevated under diabetic conditions. Our results also highlight that p-coumaric acid is an efficient compound with antioxidant properties and improves the diabetes-induced change in lipid peroxidation and activities of antioxidant enzymes: catalase, glutathione-S-transferase and superoxide dismutase. p-Coumaric acid thus possesses the potential to prevent diabetic nephropathy by reducing oxidative stress and can thus serve as a potential drug target for pharmaceutical companies.

An evaluation on potential anti-oxidant and anti-inflammatory effects of Crocin

Crocin, an active ingredient derived from saffron, is one of the herbal components that has recently been considered by researchers. Crocin has been shown to have many anti-inflammatory and antioxidant properties, and therefore can be used to treat various diseases. It has been shown that Crocin has a positive effect on the prevention and treatment of cardiovascular disease, cancer, diabetes, and kidney disease. In addition, the role of this substance in COVID-19 pandemic has been identified. In this review article, we tried to have a comprehensive review of the antioxidant and anti-inflammatory effects of Crocin in different diseases and different tissues. In conclusion, Crocin may be helpful in pathological conditions that are associated with inflammation and oxidative stress.

Mechanism of Cordyceps sinensis and its Extracts in the Treatment of Diabetic Kidney Disease: A Review

Diabetic kidney disease (DKD) is the major reason of chronic kidney disease (CKD)-caused end-stage renal failure (ESRF), and leads to high mortality worldwide. At present, the treatment of DKD is mainly focused on controlling the hyperglycemia, proteinuria, and hypertension, but is insufficient on the effective delay of DKD progression. Cordyceps sinensis is a kind of wild-used precious Chinese herb. Its extracts have effects of nephroprotection, hepatoprotection, neuroprotection, and protection against ischemia/reperfusion-induced injury, as well as anti-inflammatory and anti-oxidant activities. According to the theory of traditional Chinese medicine, Cordyceps sinensis can tonify the lung and the kidney. Several Chinese patent medicines produced from Cordyceps sinensis are often used to treat DKD and achieved considerable efficacy. This review summarized the clinical usage of Cordyceps sinensis, as well as its mainly biological activities including anti-hyperglycemic, anti-inflammatory, immunomodulatory, anti-oxidant, anti-fibrotic activities and regulation of apoptosis.

Supplementation of conventional anti-diabetic therapy with alpha-lipoic acid prevents early development and progression of diabetic nephropathy

BACKGROUND

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease. Current pharmacological interventions only retard DN progression. Alpha-lipoic acid (ALA) is a potent antioxidant with beneficial effect in other diabetic complications. This study investigates whether ALA supplementation prevents early development and progression of DN.

METHOD

Fifty-eight male Sprague-Dawley rats were randomly assigned to healthy control and diabetic groups and subjected to overnight fasting. Type 2 diabetes mellitus (T2DM) was induced in diabetic group by intraperitoneal administration of nicotinamide (110 mg/kg) and streptozotocin (55 mg/kg). On day 3 after T2DM induction, diabetic rats received oral daily administration of ALA (60 mg/kg), gliclazide (15 mg/kg), ramipril (10 mg/kg) or drug combinations for 6 weeks. Untreated diabetic rats served as diabetic control. Blood, kidneys and pancreas were harvested for biochemical and histological analyses.

RESULT

Induction of T2DM resulted in hypoinsulinemia, hyperglycemia and renal pathology. ALA supplementation maintained β-cell function, normoinsulinemia and normoglycemia in diabetic rats, and prevented renal pathology (PAS, KIM-1, plasma creatinine, total protein, blood urea nitrogen, uric acid and urine albumin/creatinine ratio) and triglycerides level compared to diabetic control (p < 0.001). Additionally, ALA supplementation significantly prevented elevated serum and tissue malondialdehyde, collagen deposition, α-SMA expression, apoptosis and serum IL-1β and IL-6 levels while it markedly increased renal glutathione content and plasma HDL-C compared to diabetic control group (p < 0.001).

CONCLUSION

ALA supplementation prevents early development and progression of DN by exerting anti-hyperglycemic, antioxidant, anti-inflammatory, anti-fibrotic and anti-apoptotic effects. Our findings provide additional option for clinical treatment of DN in T2DM patients.

Nephroprotective effect of magnesium isoglycyrrhizinate against arsenic trioxide‑induced acute kidney damage in mice

Magnesium isoglycyrrhizinate (MgIG) has anti-inflammatory, antioxidative, antiviral and anti-hepatotoxic effects. However, protective effects of MgIG against renal damage caused by arsenic trioxide (ATO) have not been reported. The present study aimed to clarify the protective function of MgIG on kidney damaged induced by ATO. Other than the control group and the group treated with MgIG alone, mice were injected intraperitoneally with ATO (5 mg/kg/day) for 7 days to establish a mouse model of kidney damage. On the 8th day, blood and kidney tissue were collected and the inflammatory factors and antioxidants levels in the kidney tissue and serum were measured. The expression of protein levels of caspase-3, Bcl-2, Bax, Toll-like receptor-4 (TLR4) and nuclear factor-κB (NF-κB) were determined via western blot analysis. In the renal tissue of mice, ATO exposure dramatically elevated markers of oxidative stress, apoptosis and inflammation. However, MgIG could also restore the activities of urea nitrogen and creatinine to normal levels, decrease the malondialdehyde level and reactive oxygen species formation and increase superoxide dismutase, catalase and glutathione activities. MgIG also ameliorated the morphological abnormalities generated by ATO, reduced inflammation and apoptosis and inhibited the TLR4/NF-κB signaling pathway. In conclusion, MgIG may mitigate ATO-induced kidney damage by decreasing apoptosis, oxidative stress and inflammation and its mechanism may be connected to the inhibition of TLR4/NF-κB signaling.

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

Diabetes is the most prevalent disorder in the world characterized by uncontrolled high blood glucose levels and nephropathy is one of the chief complications allied with hyperglycemia. Vanillic acid; the main bioactive compound derived from natural sources such as vegetables, fruits and plants possesses various pharmacological activities such as antioxidant, anti-inflammatory and anti-proliferative. The current study was designed to investigate the antidiabetic and renoprotective effects of vanillic acid by its various pharmacological activities. Streptozotocin (50 mg/kg)/nicotinamide (110 mg/kg) was used to induce diabetes in rats. Oral administration of vanillic acid once daily for 6 weeks (25, 50 and 100 mg/kg) significantly reduced the hyperglycemia, increased liver enzymes and normalized lipid profile that was altered in diabetic rats. Moreover, vanillic acid attenuated the impaired renal function as evidenced by a reduction in serum creatinine, urea, uric acid and urinary microproteinuria levels with a concomitant increase in urinary creatinine clearance in the nephropathic rats. Diabetic rats showed a marked increase in thiobarbituric acid reactive substances (TBARS) and superoxide anion generation (SAG) along with decreased reduced glutathione (GSH) in the renal tissue which was ameliorated in the vanillic acid-treated rats. Histopathologically, vanillic acid treatment was associated with reduced damage with normalized structural changes in renal tissue. Furthermore, treatment groups showed the suppression of upregulation of nuclear factor (NF)-κB, tumor necrosis factor (TNF)-α, cyclo-oxygenase (COX)-2 and up-regulation of Nuclear factor-erythroid 2-related factor 2 (Nrf-2) in the renal tissue. In conclusion, vanillic acid's ameliorative impact on diabetic nephropathic rats may be attributed to its powerful free radical scavenging property, down-regulation of NF-κB, TNF-α, COX-2 and up-regulation of Nrf-2 proteins in renal tissue.

Treatment with crocin suppresses diabetic nephropathy progression via modulating TGF-β1 and oxidative stress in an experimental model of pinealectomized diabetic rats

One of the most common complications of diabetes is diabetic nephropathy (DN). Uncontrolled hyperglycemia leads to histopathologic alterations in the kidney that prevent normal renal function. This study aimed to explore the effects of crocin treatment via virtue of its numerous beneficial properties in streptozotocin-induced pinealectomized diabetic rats. The pinealectomy procedure was conducted on the first day of the study. On the 30th day following pinealectomy, streptozotocin (STZ) (50 mg/kg) was administered intraperitoneally in Wistar rats for induction of diabetes. Diabetes was confirmed on the 3rd day following STZ administration by determining the glucose levels. Daily crocin treatment intraperitoneally for 15 days (50 mg/kg) ameliorated impaired renal oxidant/antioxidant balance, reduced TGF-β1 immuno-staining around tubules, and promoted improvement of renal architecture. Moreover, crocin administration improved altered renal function parameters, including serum Cr and BUN, and also increased creatinine clearance. In conclusion, the protective effects of crocin on diabetic nephropathy might be associated with its powerful antioxidant properties, its ability to improve tissue antioxidant status, and its ability to prevent inflammatory pathways.

Evaluation of the Effect of Crocin on Doxorubicin-Induced Cardiotoxicity

Despite newer advances in cancer treatment, chemotherapy is still one of the most widely used treatment strategies in this field. However, this treatment strategy faces major challenges. Doxorubicin (Dox) is an effective chemotherapeutic agent used to treat various cancers. However, several studies have shown that the use of Dox in therapeutic concentrations is associated with serious side effects, such as cardiac toxicity. The use of natural products in combination with chemotherapeutic agents to reduce side effects is a novel approach, and several studies have shown promising results. In this regard, we examined the effect of Crocin on doxorubicin-induced cardiotoxicity in rat and H9c2 cell line. The in vitro model on H9C2 cells and the in vivo models on rats were treated with doxorubicin. Cell viability, DNA damage, and apoptosis were measured in H9C2 cell line in the presence and absence of Crocin. Oxidative stress and various inflammatory parameters, as well as cardiac function tests, also were assessed in doxorubicin-induced cardiotoxicity animal model in the presence and absence of Crocin. Our results showed that Crocin can significantly decrease apoptosis in H9C2 cell line through a reduction in ROS production and DNA damages. Moreover, evaluation of the effect of Crocin on doxorubicin-induced cardiotoxicity animal model showed that Crocin also can significantly reduce oxidative stress and inflammatory parameters in the serum of the animals. Assessment of cardiac function revealed that Crocin has a significant protective effect against doxorubicin-induced cardiotoxicity in the animal model. Our data indicate that Crocin significantly attenuated doxorubicin-induced cardiotoxicity. Hence, Crocin could be potentially used as an adjuvant treatment in combination with Dox to reduce cardiotoxicity.

The mechanisms of saffron (Crocus sativus') on the inflammatory pathways of diabetes mellitus: A systematic review

BACKGROUND

and amis: Diabetes is one of the major medical problems, which can lead to damage to cells or organs in various parts of the body. Saffron as herbal medicine has contained several active ingredients, including safranal, flavonoids, crocetin, and crocin, which are effective in modulating oxidative stress and inflammation, which can play the main role in reducing the effects of diabetes. However, so far, the effect of saffron on diabetes inflammation has not been evaluated in the form of systematic review studies. The purpose of this systematic study was to evaluate the evidence obtained from in-vitro, animal, and clinical trials studies on the effects of saffron on inflammation in diabetes.

METHODS

The present systematic review was conducted according to the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statements. In this systematic review, databases such as Embase, Pubmed, SCOPUS, ProQuest, and sciences direct database were searched from the beginning to February 2021. All eligible in-vitro, animal and human studies that examined the effect of saffron on inflammatory factors in diabetes were published in the form of a full article in English.

RESULTS

In the end, only 20 of the 596 articles met the criteria for analysis. Of the 20 articles, 3 were in-vitro studies, 13 were animal studies, and 4 were human studies.

CONCLUSION

The findings of this systematic study (Except for two studies) suggest that saffron supplementation with potential anti-inflammatory properties may reduce the expression of the inflammatory pathway and the production of inflammatory products in diabetes.

Intraperitoneal Lavage with Crocus sativus Prevents Postoperative-Induced Peritoneal Adhesion in a Rat Model: Evidence from Animal and Cellular Studies

Postoperative peritoneal adhesions are considered the major complication following abdominal surgeries. The primary clinical complications of peritoneal adhesion are intestinal obstruction, infertility, pelvic pain, and postoperative mortality. In this study, regarding the anti-inflammatory and antioxidant activities of Crocus sativus, we aimed to evaluate the effects of Crocus sativus on the prevention of postsurgical-induced peritoneal adhesion. Male Wistar-Albino rats were used to investigate the preventive effects of C. sativus extract (0.5%, 0.25% and 0.125% w/v) against postsurgical-induced peritoneal adhesion compared to pirfenidone (PFD, 7.5% w/v). We also investigated the protective effects of PFD (100 μg/ml) and C. sativus extract (100, 200, and 400 μg/ml) in TGF-β1-induced fibrotic macrophage polarization. The levels of cell proliferation and oxidative, antioxidative, inflammatory and anti-inflammatory, fibrosis, and angiogenesis biomarkers were evaluated both in vivo and in vitro models. C. sativus extract ameliorates postoperational-induced peritoneal adhesion development by attenuating oxidative stress [malondialdehyde (MDA)]; inflammatory mediators [interleukin- (IL-) 6, tumour necrosis factor- (TNF-) α, and prostaglandin E₂ (PGE₂)]; fibrosis [transforming growth factor- (TGF-) β1, IL-4, and plasminogen activator inhibitor (PAI)]; and angiogenesis [vascular endothelial growth factor (VEGF)] markers, while propagating antioxidant [glutathione (GSH)], anti-inflammatory (IL-10), and fibrinolytic [tissue plasminogen activator (tPA)] markers and tPA/PAI ratio. In a cellular model, we revealed that the extract, without any toxicity, regulated the levels of cell proliferation and inflammatory (TNF-α), angiogenesis (VEGF), anti-inflammatory (IL-10), M1 [inducible nitric oxide synthase (iNOS)] and M2 [arginase-1 (Arg 1)] biomarkers, and iNOS/Arg-1 ratio towards antifibrotic M1 phenotype of macrophage, in a concentration-dependent manner. Taken together, the current study indicated that C. sativus reduces peritoneal adhesion formation by modulating the macrophage polarization from M2 towards M1 cells.

Therapeutic and delivery strategies of phytoconstituents for renal fibrosis

Chronic kidney disease (CKD) is one of the most common diseases endangering human health and life. By 2030, 14 per 100,000 people may die from CKD. Renal fibrosis (RF) is an important intermediate link and the final pathological change during CKD progression to the terminal stage. Therefore, identifying safe and effective treatment methods for RF has become an important goal. In 2018, the World Health Organization introduced traditional Chinese medicine into its effective global medical program. Various phytoconstituents that affect the RF process have been extracted from different plants. Here, we review the potential therapeutic capabilities of active phytoconstituents in RF treatment and discuss how phytoconstituents can be structurally modified or combined with other ingredients to enhance efficiency and reduce toxicity. We also summarize phytoconstituent delivery strategies to overcome renal barriers and improve bioavailability and targeting.

The cardiovascular-protective properties of saffron and its potential pharmaceutical applications: A critical appraisal of the literature

Saffron, the dried stigma of Crocus sativus L., is used in traditional medicine for its healing properties and the treatment of various pathological conditions. The present literature review aimed to summarize and evaluate the preclinical and clinical data regarding the protective effects and mechanisms of saffron and its main components (crocin, crocetin, safranal) on cardiovascular risk factors and diseases. Many in vitro and animal studies have been conducted implicating antioxidant, hypolipidemic, anti-diabetic, and antiinflammatory impact of saffron and its constituents. Notably, there is evidence of direct atherosclerosis regression and stabilization in valid atherosclerosis-prone animal models. However, current clinical trials have shown mostly weak effects of saffron and its constituents on cardiovascular risk factors: (a) Modest lowering of fasting blood glucose, without significant reduction of HbA1c in type 2 diabetic patients, (b) moderate/controversial hypolipidemic effects, (c) negligible hypotensive effect, and (d) inconsistent modification of metabolic syndrome parameters. There are important drawbacks in clinical trial design, including the absence of pharmacokinetic/pharmacodynamic tests, the wide variance of doses and cohorts' characteristics, the small number of patients, the short duration. Therefore, large, properly designed, high-quality clinical trials, focusing on specific conditions are required to evaluate the biological/pharmacological activities and firmly establish the clinical efficacy of saffron and its possible therapeutic uses in cardiovascular diseases.

Crocin alleviates the inflammation and oxidative stress responses associated with diabetic nephropathy in rats via NLRP3 inflammasomes

AIM

Currently, drugs for the treatment of diabetic nephropathy (DN) are lacking. This study aimed to explore the protective effect of crocin on DN.

MAIN METHODS

Diabetes was induced in rats by streptozotocin (STZ), and changes in metabolism and renal parameters after crocin treatment were measured. Dihydroethidium (DHE) fluorescence and superoxide generation were used to detect the levels of reactive oxygen species (ROS) in rat renal tissues. Enzyme-linked immunosorbent assay was used to measure changes inflammation-related factors with crocin treatment. In addition, the expression of Nod-like receptor family pyrin domain-containing 3 (NLRP3) signaling pathway components was detected by western blot analysis, qRT-PCR, and immunohistochemistry.

KEY FINDINGS

Crocin lowered blood sugar, increased serum insulin levels, and improved diabetes-related symptoms, including kidney dysfunction. Masson trichrome staining revealed that crocin could improve renal tissue fibrosis caused by hyperglycemia. Moreover, crocin inhibited ROS production in renal tissues and generally inhibited the production of the proinflammatory factors TNF-α, IL-1β, and IL-18. Crocin exerted these functions by inhibiting the expression of the NLRP3 inflammasome in DN rats.

SIGNIFICANCE

Crocin alleviates DN related oxidative stress and inflammation by inhibiting NLRP3 inflammasomes. Our results provide a new target for the treatment of DN.

Ameliorative effects of crocin on the inflammation and oxidative stress-induced kidney damages by experimental periodontitis in rat

Objective(s):

The present study aimed to investigate the effects of periodontitis on kidneys and the protective role of crocin in periodontitis-induced kidney damage.

Materials and Methods:

Ethics committee approval was obtained and 30 Wistar rats were randomly divided into 3 groups of 10 rats: Control (C), Periodontitis (P), and Periodontitis + Crocin (P + Cr). After the treatments, rat kidney tissues were incised under anesthesia and blood samples were collected. Biochemical and histopathological analyses were conducted on the samples.

Results:

Malondialdehyde (MDA), total oxidant status (TOS), and oxidative stress index (OSI) increased in P group rat kidney tissues; urea, creatinine, Tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin 1β (IL-1β) levels increased in the serum; glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and total antioxidant status (TAS) levels were reduced in rat kidney tissues, and renal histopathology deteriorated. In the P + Cr group, we observed improvements in biochemical and histopathological parameters when compared with the P group.

Conclusion:

Periodontitis (P) led to deterioration in oxidative stress parameters and histopathology by increasing the oxidants in kidney tissue. P also led to inflammation in the blood of the rats. Periodontitis + Crocin (P + Cr) administration alleviated the effects of P due to powerful antioxidant anti-inflammatory properties. Cr could be employed as a protective agent in P-induced inflammation and oxidative damage.

Amelioration of STZ-induced nephropathy in diabetic rats by saffron hydro alcoholic extract

OBJECTIVES

Type 1 diabetes is one of the most important causes of microvascular complications such as nephropathy. On other hand, the use of herbal medicines is more affordable and has fewer side effects. Therefore, this study was conducted to assessment the therapeutic effect of saffron in diabetic nephropathy by regulating the expression of CTGF and RAGE genes as well as oxidative stress in rats with type 1 diabetes.

METHODS

In this study, we used 24 Wistar rats in four groups. To induce diabetes, we used a 55 mg/kg.bw dose of streptozotocin intraperitoneally. Type 1 diabetic rats were administered saffron (20 and 40 mg/kg/day) by gavage once daily for 42 days. Finally, serum urea, creatinine, albumin and SOD, MDA levels in kidney tissue were measured using spectrophotometric methods and CTGF and RAGE gene expression in kidney tissue was measured using real-time PCR method.

RESULTS

Diabetes significantly increases serum FBG, urea, creatinine and decreases albumin (p<0.001). AS well as increased the CTGF and RAGE genes expression, MDA level and decreased the SOD activity in the kidney tissue (p<0.001). Serum urea, creatinine, albumin was significantly ameliorated by saffron (p<0.001). It was shown the saffron significantly decrease the kidney expression CTGF and RAGE genes and MDA level and increased the SOD activity (p<0.001). Also, it was found that the beneficial effects of the saffron were dose-dependent (p<0.05).

CONCLUSIONS

The results of this study suggest that saffron as an adjunct therapy may prevent development and treatment of diabetic nephropathy by regulating the expression of the CTGF and RAGE genes and oxidative stress.

Inflammatory markers response to crocin supplementation in patients with type 2 diabetes mellitus: A randomized controlled trial

Inflammation and oxidative stress is a risk factor for the development of long-term consequences in patients with type 2 diabetes mellitus (T2DM). This study was designed to investigate the effects of crocin consumption on oxidative stress and inflammatory markers in patients with T2DM. In this clinical trial with a parallel-group design, 50 patients with T2DM were randomly assigned to either the crocin or the placebo group. The crocin group received 15 mg crocin twice daily, whereas the placebo group received corresponding placebos. At baseline and the end of week 12, serum high sensitive C-reactive protein (hs-CRP), interleukin-6 (IL-6), tumor necrosis factor-ɑ (TNF-ɑ), nuclear factor-κB (NF-κB), and malondialdehyde (MDA) were measured. Compared with placebo group, crocin reduced hs-CRP (-1.03 vs. 1.42, p = .007), TNF-ɑ (-0.8 vs. 0.28, p = .009), and NF-κB (-0.39 vs. 0.01, p = .047) after 12 weeks intervention; these improvements were also significant in comparison with the baseline values. Plasma IL-6 decreased significantly in the crocin group at the end of week 12 compared to baseline (p = .037), whereas no significant change was observed in the placebo group. Plasma concentration of MDA did not change within and between groups after intervention. This study indicates that daily administration of 30 mg crocin supplement to patients with T2DM reduces the concentrations of hs-CRP, TNF-ɑ, and NF-κB which are involved in the pathogenesis of complications of T2DM.

Antioxidant and Anti-Inflammatory Effects of Crocin Ameliorate Doxorubicin-Induced Nephrotoxicity in Rats

Doxorubicin is a drug that belongs to the anthracycline antibiotics. Nephrotoxicity is one of the serious side effects of doxorubicin treatment. Crocin, which is one of the most bioactive components of saffron, has antioxidant, anti-inflammatory, and antitumor effects. The current study was aimed at investigating the possible protective effects of crocin against doxorubicin-induced nephrotoxicity to elucidate the underlying mechanism of this effect. The study included four groups, six rats in each group: normal control, crocin control, doxorubicin, and crocin/doxorubicin. Doxorubicin and crocin/doxorubicin groups received intraperitoneal injections of doxorubicin (3.5 mg/kg twice weekly for 3 weeks). Rats in the crocin control group and the crocin/doxorubicin group were treated with intraperitoneal injections of crocin (100 mg/kg body weight per day) for 3 weeks. Biomarkers of kidney function and oxidative stress as well as the abundance of mRNA for nuclear factor-κβ and inducible nitric oxide synthase were evaluated. In addition, the abundance of cyclooxygenase 2 and tumor necrosis factor α immunoreactivity was evaluated. Crocin treatment had renoprotective effects manifested by significant improvement in kidney function as well as a reduction in the abundance of biomarkers of oxidative stress markers and inflammatory mediators. In conclusion, crocin has a protective effect against doxorubicin-induced nephrotoxicity in rats by serving as an antioxidant and attenuating the expression of NF-κB, iNOS, COX2, and TNFα.

Toll-like receptor 4: An attractive therapeutic target for acute kidney injury

Acute kidney injury (AKI) is a progressive renal complication which significantly affects the patient's life with huge economic burden. Untreated acute kidney injury eventually progresses to a chronic form and end-stage renal disease. Although significant breakthroughs have been made in recent years, there are still no effective pharmacological therapies for the treatment of acute kidney injury. Toll-like receptor 4 (TLR4) is a well-characterized pattern recognition receptor, and increasing evidence has shown that TLR4 mediated inflammatory response plays a pivotal role in the pathogenesis of acute kidney injury. The expression of TLR4 has been seen in resident renal cells, including podocytes, mesangial cells, tubular epithelial cells and endothelial cells. Activation of TLR4 signaling regulates the transcription of numerous pro-inflammatory cytokines and chemokines, resulting in renal inflammation. Therefore, targeting TLR4 and its downstream effectors could serve as an effective therapeutic intervention to prevent renal inflammation and subsequent kidney damage. For the first time, this review summarizes the literature on acute kidney injury from the perspective of TLR4 from year 2010 to 2020. In the current review, the role of TLR4 signaling pathway in AKI with preclinical evidence is discussed. Furthermore, we have highlighted several compounds of natural and synthetic origin, which have the potential to avert the renal TLR4 signaling in preclinical AKI models and have shown protection against AKI. This scientific review provides new ideas for targeting TLR4 in the treatment of AKI and provides strategies for the drug development against AKI.

Inhibitory Effect of Crocin Against Gastric Carcinoma via Regulating TPM4 Gene

Background

Gastric cancer (GC) is one of the most common malignant tumors and the second most frequent cause of cancer death worldwide. Crocin is a kind of bioactive constituent found in the stigmas of saffron, which has shown various pharmacological activities.

Methods

In this study, we investigated the inhibitory effect of crocin on gastric cancer AGS cells proliferation and explored the underlying mechanism. A series of methods were used including cell counting kit assay, gene microarray analysis, qRT-PCR, Celigo image cytometry, cell clone formation assay, Western blot, and cell xenograft growth in vivo.

Results

The results indicated that crocin inhibited AGS cells proliferation and promoted cell apoptosis. Further studies suggested that crocin decreased a series of genes expression, among which TPM4 gene downregulation inhibited the tumor cells proliferation and tumor growth in mice, and overexpression of TPM4 gene abolishes the inhibitory effect of crocin. Further study using microarray analysis suggested that knocking down of TPM4 altered genes related to the proliferation and apoptosis of cells.

Discussion

Crocin could inhibit the gastric cancer cells AGS cells proliferation by regulating TPM4 gene expression, and TPM4 may be a promising therapeutic target for GC treatment.

Forsythoside A Alleviates High Glucose-Induced Oxidative Stress and Inflammation in Podocytes by Inactivating MAPK Signaling via MMP12 Inhibition

BACKGROUND

Podocyte injury serves an important role during the progression of diabetic nephropathy (DN). The aim of this study was to investigate the effects of forsythoside A (FA) on high glucose (HG)-induced podocyte injury and to identify the possible mechanisms.

METHODS

MPC-5 podocytes were cultured under HG conditions. After exposure to different doses of FA, cell viability and apoptosis were respectively evaluated with CCK-8 assay and flow cytometry. Then, the levels of oxidative stress-related markers and inflammatory factors were examined by corresponding kits. Western blot analysis was employed to detect the expression of Nox2, Nox4, COX-2, iNOS and matrix metalloproteinases 12 (MMP12). Subsequently, MMP12 was overexpressed to assess whether the effects of FA on HG-stimulated podocyte injury were mediated by MMP12 and MAPK signaling.

RESULTS

Results indicated that FA dose-dependently elevated cell viability, reduced cell apoptosis in HG-induced MPC-5 cells. Additionally, FA significantly inhibited oxidative stress, which could be certified by decreased content of malondialdehyde (MDA), enhanced activities of superoxide dismutase (SOD) and catalase (CAT), and downregulated expression of Nox2 and Nox4. Moreover, notably reduced levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 were observed in FA-treated MPC-5 cells under HG conditions, accompanied by decreased COX-2 and iNOS expression. Remarkably, FA suppressed MMP12 expression in a dose-dependent manner, and the effects of FA on MPC-5 cells exposed to HG were partially counteracted by MMP12 overexpression. Mechanically, FA inactivated the expression of phospho-ERK (p-ERK), p-p38 and p-JNK, which was restored after MMP12 overexpression.

CONCLUSION

These findings demonstrate a protective mechanism of FA by inactivating MAPK signaling via MMP12 inhibition in HG-induced podocyte injury, providing a promising therapeutic candidate for the treatment of DN.

Herbal formula LLKL ameliorates hyperglycaemia, modulates the gut microbiota and regulates the gut-liver axis in Zucker diabetic fatty rats

LLKL, a new traditional Chinese medicine formula containing Edgeworthia gardneri (Wall.) Meisn., Sibiraea angustata and Crocus sativus L. (saffron), was designed to ameliorate type 2 diabetes mellitus. Despite the therapeutic benefits of LLKL, its underlying mechanisms remain elusive. This study evaluated the LLKL anti-diabetic efficacy and its effect on gut microbiota to elucidate its mechanism of action in Zucker diabetic fatty rats. We found that administration of different LLKL concentrations (4.68, 2.34 and 1.17 g/kg/d) improved several diabetic parameters after a 6-week treatment. Moreover, LLKL modulated gut microbiota dysbiosis, increased the expression of occluding and maintained intestinal epithelial homeostasis, leading to a reduction in LPS, TNF-α and IL-6 levels. Hepatic transcriptomic analysis showed that the Toll-like receptor signalling pathway was markedly enriched by LLKL treatment. RT-qPCR results validated that LLKL treatment decreased the expressions of TLR4, MyD88 and CTSK. Furthermore, a gene set enrichment analysis indicated that LLKL enhanced the insulin signalling pathway and inhibited glycerolipid metabolism and fatty acid metabolism, which were verified by the liver biochemical analysis. These findings demonstrate that LLKL ameliorates hyperglycaemia, modulates the gut microbiota and regulates the gut-liver axis, which might contribute to its anti-diabetic effect.

Association Between Cannabinoid Receptor-1 Gene Polymorphism and the Risk of Diabetic Nephropathy Among Patients with Type 2 Diabetes Mellitus

Background

The cannabinoid receptor 1 (CNR1) gene polymorphism is reportedly associated with components of metabolic syndrome and coronary artery diseases in patients with type 2 diabetes mellitus (T2DM). We investigated whether the common variant rs10493353 polymorphism is associated with diabetic nephropathy (DN) in T2DM patients.

Patients and Methods

T2DM patients with DN were enrolled as a case group, and patients with only T2DM as a control group. Demographic data and biochemical parameters were collected. The polymerase chain reaction-based restriction fragment length polymorphism technique was used for genotyping. The odds ratio and 90% confidence interval were calculated to assess the association between genotypes and the risk of DN.

Results

In total, 320 T2DM patients and 320 DN patients were enrolled. Compared with T2DM patients, the DN patients have a significantly larger body mass index (BMI), longer duration of disease, and higher proportions of smokers, drinkers, and hypertension. The risk of DN was significantly decreased by genotypes AA (OR=0.39, 95% CI=0.23–0.67) and GA (OR=0.53, 95% CI=0.37–0.75) vs GG (codominant model), GA/AA vs GG (OR=0.49, 95% CI=0.35–0.67; dominant model), AA vs GG/GA (OR=0.47, 95% CI=0.28–0.80; recessive model), and the A allele (OR=0.52, 95% CI=0.40–0.68; allele model). Multiple logistic regressions still show significant levels. Negative interactions were found between gene and clinical parameters, including drinking, smoking, BMI, and hypertension.

Conclusion

The A allele of CNR1 gene rs10493353 may be a protective factor for DN in T2DM patients. The risk factors of DN can affect the protective role of A allele in the progression of DN.

Collagen IV, a promising serum biomarker for evaluating the prognosis of revascularization in a 2-kidney, 1-clip hypertensive rat model

OBJECTIVES

The goal of this study was to investigate the expression of serum collagen IV and its value for evaluating the prognosis of revascularization in a 2-kidney, 1-clip hypertensive rat model.

METHODS

A total of 40 Sprague-Dawley rats were randomly and evenly divided into a control group and 3-, 10- and 20-day (D) groups (namely, the ischaemic time for 3, 10 and 20 days, respectively). The systolic blood pressure and laboratory values such as serum creatinine and collagen IV levels were measured before and after clipping the renal artery. Histological Masson staining and immunohistochemical staining of collagen IV were conducted in a kidney specimen from each group to assess the severity of renal fibrosis and the level of collagen IV expression.

RESULTS

After clipping, systolic blood pressure in the 3D, 10D and 20D groups increased significantly from 108 ± 8 to 126 ± 7 and from 153 ± 8 to 157 ± 6 mmHg, respectively (10D vs 20D group, P = 0.224; between other groups, P < 0.001). The expression of serum creatinine in the 3D, 10D and 20D groups increased significantly from 35.39 ± 5.64 to 57.53 ± 7.05, 101.86 ± 8.94 and 119.76 ± 9.37 mmol/l, respectively (between each group: P < 0.001). Serum collagen IV levels in the 10D and 20D groups increased significantly from 38.5 ± 10.4 to 60.8 ± 15.0 and 87.3 ± 11.5 ng/ml, respectively (control vs 3D group, P = 0.718; between other groups, P < 0.001). The Masson staining indicated that sclerotic changes in the glomeruli of the 10D and 20D groups significantly increased from 2.20 ± 1.03 to 15.20 ± 5.03 and 28.20 ± 7.07%, respectively (control vs 3D group, P = 0.175; between other groups, P < 0.001). The grade of tubulointerstitial damage in the 3D, 10D and 20D groups increased significantly from 0.30 ± 0.48 to 1.90 ± 0.74, 1.80 ± 0.79 and 3.20 ± 0.79, respectively (3D vs 10D group, P = 0.755; between other groups, P < 0.001). The semi-quantification from immunohistochemical staining indicated that the percentage of collagen IV positive areas in the 3D, 10D and 20D groups increased significantly from 3.50 ± 1.58 to 8.60 ± 2.11, 16.60 ± 8.55 and 23.10 ± 6.15, respectively (control vs 3D group, P = 0.043; 3D vs 10D group, P = 0.002; 10D vs 20D group, P = 0.011; between other groups, P < 0.001). The area under the curve of the receiver operating characteristic curve was 0.783 (P = 0.008; 95% confidence interval 0.634-0.932). There were positive associations of serum collagen IV levels with systolic blood pressure, serum creatinine and collagen IV quantification in kidney with correlation coefficients of 0.665, 0.775 and 0.628, respectively (P < 0.001).

CONCLUSIONS

As the clear ischaemia time-response relationship identified in our study indicates, the increase in serum collagen IV levels may be a satisfactory biomarker to indicate a poor prognosis of renal artery revascularization in a 2-kidney, 1-clip hypertensive rat model. However, it is perhaps not a good early biomarker for the early detection of renovascular hypertension.