Quercetin preserves redox status and stimulates mitochondrial function in metabolically-stressed HepG2 cells

The flavonoid quercetin decreases ACE2 and TMPRSS2 expression but not SARS-CoV-2 infection in cultured human lung cells

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) binds to angiotensin-converting enzyme 2 (ACE2) on host cells, via its spike protein, and transmembrane protease, serine 2 (TMPRSS2) cleaves the spike-ACE2 complex to facilitate virus entry. As rate-limiting steps for virus entry, modulation of ACE2 and/or TMPRSS2 may decrease SARS-CoV-2 infectivity and COVID-19 severity. In silico modeling suggested the natural bioactive flavonoid quercetin can bind to ACE2 and a recent randomized clinical trial demonstrated that oral supplementation with quercetin increased COVID-19 recovery. A range of cultured human cells were assessed for co-expression of ACE2 and TMPRSS2. Immortalized Calu-3 lung cells, cultured and matured at an air-liquid interface (Calu-3-ALIs), were established as the most appropriate. Primary bronchial epithelial cells (PBECs) were obtained from healthy adult males (N = 6) and cultured under submerged conditions to corroborate the outcomes. Upon maturation or reaching 80% confluence, respectively, the Calu-3-ALIs and PBECs were treated with quercetin, and mRNA and protein expression were assessed by droplet digital PCR and ELISA, respectively. SARS-CoV-2 infectivity, and the effects of pre- and co-treatment with quercetin, was assessed by median tissue culture infectious dose assay. Quercetin dose-dependently decreased ACE2 and TMPRSS2 mRNA and protein in both Calu-3-ALIs and PBECs after 4 h, while TMPRSS2 remained suppressed in response to prolonged treatment with lower doses (twice daily for 3 days). Quercetin also acutely decreased ADAM17 mRNA, but not ACE, in Calu-3-ALIs, and this warrants further investigation. Calu-3-ALIs, but not PBECs, were successfully infected with SARS-CoV-2; however, quercetin had no antiviral effect, neither directly nor indirectly through downregulation of ACE2 and TMPRSS2. Calu-3-ALIs were reaffirmed to be an optimal cell model for research into the regulation of ACE2 and TMPRSS2, without the need for prior genetic modification, and will prove valuable in future coronavirus and respiratory infectious disease work. However, our data demonstrate that a significant decrease in the expression of ACE2 and TMPRSS2 by a promising prophylactic candidate may not translate to infection prevention.

Exploring the therapeutic potential of quercetin in cancer treatment: Targeting long non-coding RNAs

The escalating global incidence of cancer, which results in millions of fatalities annually, underscores the pressing need for effective pharmacological interventions across diverse cancer types. Long noncoding RNAs (lncRNAs), a class of RNA molecules that lack protein-coding capacity but profoundly impact gene expression regulation, have emerged as pivotal players in key cellular processes, including proliferation, apoptosis, metastasis, cellular metabolism, and drug resistance. Among natural compounds, quercetin, a phenolic compound abundantly present in fruits and vegetables has garnered attention due to its significant anticancer properties. Quercetin demonstrates the ability to inhibit cancer cell growth and induce apoptosis-a process often impaired in malignant cells. In this comprehensive review, we delve into the therapeutic potential of quercetin in cancer treatment, with a specific focus on its intricate interactions with lncRNAs. We explore how quercetin modulates lncRNA expression and function to exert its anticancer effects. Notably, quercetin suppresses oncogenic lncRNAs that drive cancer development and progression while enhancing tumor-suppressive lncRNAs that impede cancer growth and dissemination. Additionally, we discuss quercetin's role as a chemopreventive agent, which plays a crucial role in mitigating cancer risk. We address research challenges and future directions, emphasizing the necessity for in-depth mechanistic studies and strategies to enhance quercetin's bioavailability and target specificity. By synthesizing existing knowledge, this review underscores quercetin's promising potential as a novel therapeutic strategy in the ongoing battle against cancer, offering fresh insights and avenues for further investigation in this critical field.

Natural products as pharmacological modulators of mitochondrial dysfunctions for the treatment of diabetes and its complications: An update since 2010

Diabetes, characterized as a well-known chronic metabolic syndrome, with its associated complications pose a substantial and escalating health and healthcare challenge on a global scale. Current strategies addressing diabetes are mainly symptomatic and there are fewer available curative pharmaceuticals for diabetic complications. Thus, there is an urgent need to identify novel pharmacological targets and agents. The impaired mitochondria have been associated with the etiology of diabetes and its complications, and the intervention of mitochondrial dysfunction represents an attractive breakthrough point for the treatments of diabetes and its complications. Natural products (NPs), with multicenter characteristics, multi-pharmacological activities and lower toxicity, have been caught attentions as the modulators of mitochondrial functions in the therapeutical filed of diabetes and its complications. This review mainly summarizes the recent progresses on the potential of 39 NPs and 2 plant-extracted mixtures to improve mitochondrial dysfunction against diabetes and its complications. It is expected that this work may be useful to accelerate the development of innovative drugs originated from NPs and improve upcoming therapeutics in diabetes and its complications.

Role of Mediterranean diet in endocrine diseases: a joint overview by the endocrinologist and the nutritionist

PURPOSE

The purpose of this review is to examine the current evidence on the potential role of Mediterranean diet (MD) in the prevention and management of endocrine disorders and to highlight the importance of interdisciplinary collaboration between endocrinologists and nutritionists.

METHODS

A literature search was conducted using PubMed and Google Scholar databases to identify relevant studies published in English. Studies were selected based on their relevance to the role of MD in the prevention and management of endocrine disorders. The search terms included "Mediterranean diet," "endocrine disorders," "thyroid disorders," "gonadal disorders," and "neuroendocrine tumors".

RESULTS

The studies reviewed suggest that MD may have a beneficial effect in the prevention and management of various endocrine disorders, including thyroid disorders, gonadal disorders, and neuroendocrine tumors. MD has been associated with decreased risk of nodular thyroid disease and thyroid cancer, improved male and female reproductive health, and a potential role in the management of neuroendocrine tumors. MD's anti-inflammatory and antioxidant properties, as well as its high levels of phytochemicals, may play a role in its beneficial effects.

CONCLUSION

Interdisciplinary collaboration between endocrinologists and nutritionists is essential for the optimal management of endocrine disorders, including the potential role of MD in their prevention and management. While further research is needed, the current evidence suggests that MD may have a protective effect against endocrine disorders, and its incorporation into dietary recommendations may be beneficial.

Jian-Pi-Yi-Shen formula alleviates renal fibrosis by restoring NAD+ biosynthesis in vivo and in vitro

BACKGROUND

Patients with chronic kidney disease (CKD) lack efficacious treatment. Jian-Pi-Yi-Shen formula (JPYSF) has demonstrated significant clinical efficacy in treating CKD for decades. However, its renoprotective mechanism has not been fully elucidated. This study aimed to determine whether JPYSF could delay renal fibrosis progression in CKD by restoring nicotinamide adenine dinucleotide (NAD+) biosynthesis.

METHODS

Adenine-diet feeding was used to model CKD in C57BL/6 mice. JPYSF was orally administered for 4 weeks. Human proximal tubular epithelial cells (HK-2) cells were stimulated with transforming growth factor-β1 (TGF-β1) with or without JPYSF treatment. Renal function of mice was assessed by serum creatinine and blood urea nitrogen levels. Renal histopathological changes were assessed using Periodic acid-Schiff and Masson's trichrome staining. Cell viability was assessed using a cell counting kit-8 assay. NAD+ concentrations were detected by a NAD+/NADH assay kit. Western blotting, immunohistochemistry, and immunofluorescence were employed to examine fibrosis-related proteins and key NAD+ biosynthesis enzymes expression in the CKD kidney and TGF-β1-induced HK-2 cells.

RESULTS

JPYSF treatment could not only improve renal function and pathological injury but also inhibit renal fibrosis in CKD mice. Additionally, JPYSF reversed fibrotic response in TGF-β1-induced HK-2 cells. Moreover, JPYSF rescued the decreased NAD+ content in CKD mice and TGF-β1-induced HK-2 cells through restoring expression of key enzymes in NAD+ biosynthesis, including quinolinate phosphoribosyltransferase, nicotinamide mononucleotide adenylyltransferase 1, and nicotinamide riboside kinase 1.

CONCLUSIONS

JPYSF alleviated renal fibrosis in CKD mice and reversed fibrotic response in TGF-β1-induced HK-2 cells, which may be related to the restoration of NAD+ biosynthesis.

Anti-inflammatory reprogramming of microglia cells by metabolic modulators to counteract neurodegeneration; a new role for Ranolazine

Microglia chronic activation is a hallmark of several neurodegenerative diseases, including the retinal ones, possibly contributing to their etiopathogenesis. However, some microglia sub-populations have anti-inflammatory and neuroprotective functions, thus making arduous deciphering the role of these cells in neurodegeneration. Since it has been proposed that functionally different microglia subsets also rely on different metabolic routes, we hypothesized that modulating microglia metabolism might be a tool to enhance their anti-inflammatory features. This would have a preventive and therapeutic potential in counteracting neurodegenerative diseases. For this purpose, we tested various molecules known to act on cell metabolism, and we revealed the anti-inflammatory effect of the FDA-approved piperazine derivative Ranolazine on microglia cells, while confirming the one of the flavonoids Quercetin and Naringenin, both in vitro and in vivo. We also demonstrated the synergistic anti-inflammatory effect of Quercetin and Idebenone, and the ability of Ranolazine, Quercetin and Naringenin to counteract the neurotoxic effect of LPS-activated microglia on 661W neuronal cells. Overall, these data suggest that using the selected molecules -also in combination therapies- might represent a valuable approach to reduce inflammation and neurodegeneration while avoiding long term side effects of corticosteroids.

Therapeutic application of natural products: NAD+ metabolism as potential target

BACKGROUND

Nicotinamide adenine dinucleotide (NAD⁺) metabolism is involved in the entire physiopathological process and is critical to human health. Long-term imbalance in NAD⁺ homeostasis is associated with various diseases, including non-alcoholic fatty liver disease, diabetes mellitus, cardiovascular diseases, neurodegenerative disorders, aging, and cancer, making it a potential target for effective therapeutic strategies. Currently, several natural products that target NAD⁺ metabolism have been widely reported to have significant therapeutic effects, but systematic summaries are lacking.

PURPOSE

To summarize the latest findings on the prevention and treatment of various diseases through the regulation of NAD⁺ metabolism by various natural products in vivo and in vitro models, and evaluate the toxicities of the natural products.

METHODS

PubMed, Web of Science, and ScienceDirect were searched using the keywords "natural products sources," "toxicology," "NAD⁺ clinical trials," and "NAD⁺," and/or paired with "natural products" and "diseases" for studies published within the last decade until January 2023.

RESULTS

We found that the natural products mainly include phenols (curcumin, cyclocurcumin, 4-hydroxybenzyl alcohol, salvianolic acid B, pterostilbene, EGCG), flavonoids (pinostrobin, apigenin, acacetin, tilianin, kaempferol, quercetin, isoliquiritigenin, luteolin, silybin, hydroxysafflor yellow A, scutellarin), glycosides (salidroside), quinones (emodin, embelin, β-LAPachone, shikonin), terpenoids (notoginsenoside R1, ginsenoside F2, ginsenoside Rd, ginsenoside Rb1, ginsenoside Rg3, thymoquinone, genipin), pyrazines (tetramethylpyrazine), alkaloids (evodiamine, berberine), and phenylpropanoids (ferulic acid). These natural products have antioxidant, energy-producing, anti-inflammatory, anti-apoptotic and anti-aging effects, which mainly influence the NAMPT/NAD⁺/SIRT, AMPK/SIRT1/PGC-1α, Nrf2/HO-1, PKCs/PARPs/NF-κB, and AMPK/Nrf2/mTOR signaling pathways, thereby regulating NAD⁺ metabolism to prevent and treat various diseases. These natural products have been shown to be safe, tolerable and have fewer adverse effects in various in vivo and in vitro studies and clinical trials.

CONCLUSION

We evaluated the toxic effects of natural products and summarized the available clinical trials on NAD⁺ metabolism, as well as the recent advances in the therapeutic application of natural products targeting NAD⁺ metabolism, with the aim to provide new insights into the treatment of multiple disorders.

HM-Chromanone Alleviates Hyperglycemia by Protecting Pancreatic Islet Cells in Streptozotocin-Induced Diabetic Mice

We examined the effects of HM-chromanone (HMC) on alleviating hyperglycemia and protecting pancreatic β-cells from streptozotocin (STZ)-induced damage in C57BL/6J mice. HMC was administered to STZ-induced diabetic mice at 10 or 30 mg/kg, for 14 days. Thereafter, changes in fasting blood glucose levels, insulin-secretion, histopathological examination of pancreas islet cell and apoptotic protein levels, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay were determined. The results revealed that HMC dose-dependently improved blood glucose concentrations and alleviated pancreatic islet cells damage. In diabetic mice, degeneration of the islet cells was observed wherein they appeared shrunken, with hyaline deterioration, nuclear dissolution, and condensation. However, morphology of the islet cell was restored, and nuclei were visibly rounded in the HMC (30 mg/kg)-administered diabetic mice. In addition, β-cell numbers were markedly increased in HMC mice compared to STZ-induced diabetic mice, and the number of cells stained with glucagon was decreased. HMC markedly decreased the expression of proapoptotic proteins and increased antiapoptotic proteins, and the number of apoptotic cells detected by TUNEL was elevated. HMC decreased expression of interleukin (IL)-1β, IL-6, and tumor necrosis factor-α in diabetic mice. Moreover, HMC increased antioxidant-enzymes activity, and decreased reactive oxygen species generation. In conclusion, the results demonstrate the potential of HMC to alleviate hyperglycemia by protecting the pancreatic β-cells in diabetic mice.

Natural flavonoids alleviate glioblastoma multiforme by regulating long non-coding RNA

Glioblastoma multiforme (GBM) is one of the most common primary malignant brain tumors in adults. Due to the poor prognosis of patients, the median survival time of GBM is often less than 1 year. Therefore, it is very necessary to find novel treatment options with a good prognosis for the treatment or prevention of GBM. In recent years, flavonoids are frequently used to treat cancer. It is a new attractive molecule that may achieve this promising treatment option. Flavonoids have been proved to have many biological functions, such as antioxidation, prevention of angiogenesis, anti-inflammation, inhibition of cancer cell proliferation, and protection of nerve cells. It has also shown the ability to regulate long non-coding RNA (LncRNA). Studies have confirmed that flavonoids can regulate epigenetic modification, transcription, and change microRNA (miRNA) expression of GBM through lncRNA at the gene level. It also found that flavonoids can induce apoptosis and autophagy of GBM cells by regulating lncRNA. Moreover, it can improve the metabolic abnormalities of GBM, interfere with the tumor microenvironment and related signaling pathways, and inhibit the angiogenesis of GBM cells. Eventually, flavonoids can block the tumor initiation, growth, proliferation, differentiation, invasion, and metastasis. In this review, we highlight the role of lncRNA in GBM cancer progression and the influence of flavonoids on lncRNA regulation. And emphasize their expected role in the prevention and treatment of GBM.

Quercetin alleviates cyclophosphamide-induced premature ovarian insufficiency in mice by reducing mitochondrial oxidative stress and pyroptosis in granulosa cells

BACKGROUND

Exposure to cyclophosphamide (CTX) induces premature ovarian insufficiency (POI). Quercetin is a natural flavonoid that exhibits anti-inflammatory and antioxidant properties, and its antioxidant activity is correlated with POI. However, the mechanism underlying its protective role in CTX-induced ovarian dysfunction is unclear. This study aimed to explore whether quercetin can protect ovarian reserves by activating mitochondrial biogenesis and inhibiting pyroptosis.

METHODS

Thirty-six female C57BL/6 mice were randomly subdivided into six groups. Except for the control group, all groups were injected with 90 mg/kg CTX to establish a POI model and further treated with coenzyme 10 or various doses of quercetin. The mice were sacrificed 48 h after 10 IU pregnant mare serum gonadotropin was injected four weeks after treatments. We used enzyme-linked immunosorbent assays to detect serum hormone expression and light and transmission electron microscopy to assess ovarian tissue morphology and mitochondria. Additionally, we tested oxidant and antioxidant levels in ovarian tissues and mitochondrial function in granulosa cells (GCs). The expression of mitochondrial biogenesis and pyroptosis-related proteins and mRNA was analyzed using western blotting and RT-qPCR.

RESULTS

Quercetin elevated serum anti-Müllerian hormone, estradiol, and progesterone levels, decreased serum follicle-stimulating hormone and luteinizing hormone levels, and alleviated ovarian pathology. It reduced the mitochondrial DNA content and mitochondrial membrane potential. Furthermore, it upregulated ATP levels and the mRNA and protein expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α), mitochondrial transcription factor A, and superoxide dismutase 2. In addition, it suppressed NOD-like receptor pyrin domain containing 3, caspase-1, interleukin-1β, and gasdermin D levels in the GCs of POI mice.

CONCLUSIONS

Quercetin protected the ovarian reserve from CTX-induced ovarian damage by reversing mitochondrial dysfunction and activating mitochondrial biogenesis via the PGC1-α pathway. Moreover, quercetin may improve ovarian functions by downregulating pyroptosis in the CTX-induced POI model. Thus, quercetin can be considered a potential agent for treating POI.

Glycolysis: The Next Big Breakthrough in Parkinson's Disease

Parkinson's disease (PD) is a common neurodegenerative disease characterized by the death of dopaminergic neurons. Its pathogenesis comprises defects in the physiological pathway of mitophagy and mutations in the genes involved in this process's regulatory mechanism. PD manifests itself with multiple motor and non-motor symptoms, and currently, there are multiple pharmacological treatments, and unconventional non-drug treatments available. The mainstay of Parkinson's disease treatment has centered around directly manipulating neural mechanisms to retain high dopamine levels, either by exogenous administration, increasing intrinsic production, or inhibiting the breakdown of dopamine. In this review, we highlight a new potential biochemical modality of treatment, treating PD through glycolysis. We highlight how terazosin (TZ), via PGK1, increases ATP levels and how enhanced glycolysis serves a neuroprotective role in PD, and compensates for damage caused by mitophagy. We also discuss the role of quercetin, a bioactive flavonoid, in preventing the development of PD, and reversing mitochondrial dysfunction but only so in diabetic patients. Thus, further research should be conducted on glycolysis as a protective target in PD that can serve to not just prevent, but also alleviate the non-dopaminergic signs and symptoms of PD.

Therapeutic application of quercetin in aging-related diseases: SIRT1 as a potential mechanism

Quercetin, a naturally non-toxic flavonoid within the safe dose range with antioxidant, anti-apoptotic and anti-inflammatory properties, plays an important role in the treatment of aging-related diseases. Sirtuin 1 (SIRT1), a member of NAD+-dependent deacetylase enzyme family, is extensively explored as a potential therapeutic target for attenuating aging-induced disorders. SIRT1 possess beneficial effects against aging-related diseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington’s disease (HD), Depression, Osteoporosis, Myocardial ischemia (M/I) and reperfusion (MI/R), Atherosclerosis (AS), and Diabetes. Previous studies have reported that aging increases tissue susceptibility, whereas, SIRT1 regulates cellular senescence and multiple aging-related cellular processes, including SIRT1/Keap1/Nrf2/HO-1 and SIRTI/PI3K/Akt/GSK-3β mediated oxidative stress, SIRT1/NF-κB and SIRT1/NLRP3 regulated inflammatory response, SIRT1/PGC1α/eIF2α/ATF4/CHOP and SIRT1/PKD1/CREB controlled phosphorylation, SIRT1-PINK1-Parkin mediated mitochondrial damage, SIRT1/FoxO mediated autophagy, and SIRT1/FoxG1/CREB/BDNF/Trkβ-catenin mediated neuroprotective effects. In this review, we summarized the role of SIRT1 in the improvement of the attenuation effect of quercetin on aging-related diseases and the relationship between relevant signaling pathways regulated by SIRT1. Moreover, the functional regulation of quercetin in aging-related markers such as oxidative stress, inflammatory response, mitochondrial function, autophagy and apoptosis through SIRT1 was discussed. Finally, the prospects of an extracellular vesicles (EVs) as quercetin loading and delivery, and SIRT1-mediated EVs as signal carriers for treating aging-related diseases, as well as discussed the ferroptosis alleviation effects of quercetin to protect against aging-related disease via activating SIRT1. Generally, SIRT1 may serve as a promising therapeutic target in the treatment of aging-related diseases via inhibiting oxidative stress, reducing inflammatory responses, and restoring mitochondrial dysfunction.

Harnessing NAD+ Metabolism as Therapy for Cardiometabolic Diseases

PURPOSE OF THE REVIEW

This review summarizes current understanding on the roles of nicotinamide adenine dinucleotide (NAD⁺) metabolism in the pathogeneses and treatment development of metabolic and cardiac diseases.

RECENT FINDINGS

NAD⁺ was identified as a redox cofactor in metabolism and a co-substrate for a wide range of NAD⁺-dependent enzymes. NAD⁺ redox imbalance and depletion are associated with many pathologies where metabolism plays a key role, for example cardiometabolic diseases. This review is to delineate the current knowledge about harnessing NAD⁺ metabolism as potential therapy for cardiometabolic diseases. The review has summarized how NAD⁺ redox imbalance and depletion contribute to the pathogeneses of cardiometabolic diseases. Therapeutic evidence involving activation of NAD⁺ synthesis in pre-clinical and clinical studies was discussed. While activation of NAD⁺ synthesis shows great promise for therapy, the field of NAD⁺ metabolism is rapidly evolving. Therefore, it is expected that new mechanisms will be discovered as therapeutic targets for cardiometabolic diseases.

Chicken heterophils extracellular traps act as early effectors against cyclopiazonic acid dependent upon NADPH oxidase, ROS and glycolysis

Cyclopiazonic acid (CPA) is a secondary metabolite produced by Aspergillus and Penicillium, which is present in contaminated crops and food, causing severe toxicity to humans and animals. Heterophil extracellular traps (HETs) are a novel host innate immune mechanism of chicken heterophils against pathogen infection. However, whether CPA can cause immunotoxicity of heterophils on HETs release remains unclear. Here, we attempt to detect the effects of CPA on HETs release, and further investigate the molecular mechanisms underlying these processes. We exposed heterophils to 2.5, 5, 10 μM CPA for 90 min. The results showed that CPA induced the release of HETs in heterophils, consisting of DNA-modified citrullinated histone 3 and elastase. The quantitative analysis of HETs content was positively correlated with CPA concentration. CPA also promoted reactive oxygen species production and phosphorylation of ERK_1/2 and p38. In addition, CPA-triggered HETs formation was reduced by NADPH oxidase, ERK_1/2, and p38 signaling pathway and glycolysis inhibitors, indicating that CPA-induced HETs were related to the production of ROS dependent on NADPH oxidase, ERK_1/2, and p38 signaling pathways, as well as glycolysis. Our study describes the underlying mechanism of CPA-induced HETs release, which may provide a further understanding of the immunotoxicology of CPA poisoning.

Mitophagy and mitochondrial dynamics in type 2 diabetes mellitus treatment

The prevalence of type 2 diabetes is associated with inflammatory bowels diseases, nonalcoholic steatohepatitis and even a spectrum of cancer such as colon cancer and liver cancer, resulting in a substantial healthcare burden on our society. Autophagy is a key regulator in metabolic homeostasis such as lipid metabolism, energy management and the balance of cellular mineral substances. Mitophagy is selective autophagy for clearing the damaged mitochondria and dysfunctional mitochondria. A myriad of evidence has demonstrated a major role of mitophagy in the regulation of type 2 diabetes and metabolic homeostasis. It is well established that defective mitophagy has been linked to the development of insulin resistance. Moreover, insulin resistance is further progressed to various diseases such as nephropathy, retinopathy and cardiovascular diseases. Concordantly, restoration of mitophagy will be a reliable and therapeutic target for type 2 diabetes. Recently, various phytochemicals have been proved to prevent dysfunctions of β-cells by mitophagy inductions during diabetes developments. In agreement with the above phenomenon, mitophagy inducers should be warranted as potential and novel therapeutic agents for treating diabetes. This review focuses on the role of mitophagy in type 2 diabetes relevant diseases and the pharmacological basis and therapeutic potential of autophagy regulators in type 2 diabetes.

Quercetin Mitigates Methamphetamine-Induced Anxiety-Like Behavior Through Ameliorating Mitochondrial Dysfunction and Neuroinflammation

Methamphetamine (MA) abuse results in neurotoxic outcomes, including increased anxiety and depression. Studies have reported an association between MA exposure and anxiety, nonetheless, the underlying mechanism remains elusive. In the present study, we developed a mouse model of anxiety-like behavior induced by MA administration. RNA-seq was then performed to profile the gene expression patterns of hippocampus (HIPP), and the differentially expressed genes (DEGs) were significantly enriched in signaling pathways related to psychiatric disorders and mitochondrial function. Based on these, mitochondria was hypothesized to be involved in MA-induced anxiety. Quercetin, as a mitochondrial protector, was used to investigate whether to be a potential treatment for MA-induced anxiety; accordingly, it alleviated anxiety-like behavior and improved mitochondrial impairment in vivo. Further experiments in vitro suggested that quercetin alleviated the dysfunction and morphological abnormalities of mitochondria induced by MA, via decreasing the levels of reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and increasing the oxygen consumption rate (OCR) and ATP production. Moreover, the study examined the effect of quercetin on astrocytes activation and neuroinflammation, and the results indicated that it significantly attenuated the activation of astrocytes and reduced the levels of IL-1β, TNFα but not IL-6. In light of these findings, quantitative evidence is presented in the study supporting the view that MA can evoke anxiety-like behavior via the induction of mitochondrial dysfunction. Quercetin exerted antipsychotic activity through modulation of mitochondrial function and neuroinflammation, suggesting its potential for further therapeutic development in MA-induced anxiety.

Diet and Male Fertility: The Impact of Nutrients and Antioxidants on Sperm Energetic Metabolism

Diet might affect male reproductive potential, but the biochemical mechanisms involved in the modulation of sperm quality remain poorly understood. While a Western diet is considered a risk factor for male infertility, the Mediterranean diet seems to protect against male infertility; moreover, the role of a vegetarian habitus in the preservation of sperm quality is controversial. The aim of this review is to analyze the molecular effects of single nutrients on sperm quality, focusing on their involvement in biochemical mechanisms related to sperm bioenergetics. It appears that diets rich in saturated fatty acids (SFA) and low in polyunsaturated fatty acids (PUFA) negatively affect sperm quality, whereas unsaturated fatty acids supplementation ameliorates sperm quality. In fact, the administration of PUFA, especially omega-3 PUFA, determined an increase in mitochondrial energetic metabolism and a reduction in oxidative damage. Carbohydrates and proteins are also nutritional modulators of oxidative stress and testosterone levels, which are strictly linked to sperm mitochondrial function, a key element for sperm quality. Moreover, many dietary natural polyphenols differentially affect (positively or negatively) the mitochondrial function, depending on their concentration. We believe that an understanding of the biochemical mechanisms responsible for sperm quality will lead to more targeted and effective therapeutics for male infertility.

A Multidrug Approach to Modulate the Mitochondrial Metabolism Impairment and Relative Oxidative Stress in Fanconi Anemia Complementation Group A

Fanconi Anemia (FA) is a rare recessive genetic disorder characterized by aplastic anemia due to a defective DNA repair system. In addition, dysfunctional energy metabolism, lipid droplets accumulation, and unbalanced oxidative stress are involved in FA pathogenesis. Thus, to modulate the altered metabolism, Fanc-A lymphoblast cell lines were treated with quercetin, a flavonoid compound, C75 (4-Methylene-2-octyl-5-oxotetrahydrofuran-3-carboxylic acid), a fatty acid synthesis inhibitor, and rapamycin, an mTOR inhibitor, alone or in combination. As a control, isogenic FA cell lines corrected with the functional Fanc-A gene were used. Results showed that: (i) quercetin recovered the energy metabolism efficiency, reducing oxidative stress; (ii) C75 caused the lipid accumulation decrement and a slight oxidative stress reduction, without improving the energy metabolism; (iii) rapamycin reduced the aerobic metabolism and the oxidative stress, without increasing the energy status. In addition, all molecules reduce the accumulation of DNA double-strand breaks. Two-by-two combinations of the three drugs showed an additive effect compared with the action of the single molecule. Specifically, the quercetin/C75 combination appeared the most efficient in the mitochondrial and lipid metabolism improvement and in oxidative stress production reduction, while the quercetin/rapamycin combination seemed the most efficient in the DNA breaks decrement. Thus, data reported herein suggest that FA is a complex and multifactorial disease, and a multidrug strategy is necessary to correct the metabolic alterations.

(E)-5-hydroxy-7-methoxy-3-(2'-hydroxybenzyl)-4-chromanone isolated from Portulaca oleracea L. suppresses LPS-induced inflammation in RAW 264.7 macrophages by downregulating inflammatory factors

CONTEXT

Portulaca oleracea L. is herbaceous succulent annual plant, which belongs to the Portulacaceae family. Many studies have shown its wide spectrum of pharmacological activities such as anti-cancer and anti-diabetic effects.

OBJECTIVES

The objective of this study was to identify the anti-inflammatory effects of HM-chromanone isolated from Portulaca oleracea L. in LPS-stimulated RAW 264.7 macrophages.

MATERIALS AND METHODS

LPS (1 μg/ml)-stimulated mouse RAW 264.7 macrophages were used to assess the anti-inflammatory effect of HM-chromanone (10-50 μM). Cell viability was evaluated by MTT assay. In addition, the production of intracellular ROS, superoxide anion, lipid peroxide, NO, and PGE2, and activity of antioxidant enzymes were analyzed. The expressions of iNOS, COX-2, IκB, NF-κB, TNF-α, IL-1β and IL-6 were evaluated by western blot analysis.

RESULTS

HM-chromanone has demonstrated that there is no significant cytotoxic effect on the viability of RAW 264.7 macrophages. In LPS-stimulated RAW 264.7 cells, HM-chromanone treatment was found to significantly inhibit the production of intracellular ROS, superoxide anion and lipid peroxide, while enhancing the activity of antioxidant enzymes such as SOD, catalase, and GSH-px. Additionally, HM-chromanone treatment was observed to inhibit NO and PGE2 production by inhibiting the expression of iNOS and COX-2. Subsequently, HM-chromanone was observed to significantly suppress LPS-induced expression of IκB, NF-κB, TNF-α, IL-1β and IL-6.

DISCUSSION AND CONCLUSION

Overall, our results suggested that HM-chromanone suppresses LPS-induced inflammation in RAW 264.7 macrophages by downregulating the expression of inflammatory factors.

Quercetin as a protective agent for liver diseases: A comprehensive descriptive review of the molecular mechanism

Quercetin is the major representative of the flavonoid subgroup of flavones, with good pharmacological activities for the treatment of liver diseases, including liver steatosis, fatty hepatitis, liver fibrosis, and liver cancer. It can significantly influence the development of liver diseases via multiple targets and multiple pathways via antifat accumulation, anti-inflammatory, and antioxidant activity, as well as the inhibition of cellular apoptosis and proliferation. Despite extensive research on understanding the mechanism of quercetin in the treatment of liver diseases, there are still no targeted therapies available. Thus, we have comprehensively searched and summarized the different targets of quercetin in different stages of liver diseases and concluded that quercetin inhibited inflammation of the liver mainly through NF-κB/TLR/NLRP3, reduced PI3K/Nrf2-mediated oxidative stress, mTOR activation in autophagy, and inhibited the expression of apoptotic factors associated with the development of liver diseases. In addition, quercetin showed different mechanisms of action at different stages of liver diseases, including the regulation of PPAR, UCP, and PLIN2-related factors via brown fat activation in liver steatosis. The compound inhibited stromal ECM deposition at the liver fibrosis stage, affecting TGF1β, endoplasmic reticulum stress (ERs), and apoptosis. While at the final liver cancer stage, inhibiting cancer cell proliferation and spread via the hTERT, MEK1/ERK1/2, Notch, and Wnt/β-catenin-related signaling pathways. In conclusion, quercetin is an effective liver protectant. We hope to explore the pathogenesis of quercetin in different stages of liver diseases through the review, so as to provide more accurate targets and theoretical basis for further research of quercetin in the treatment of liver diseases.

Flavonoids and cellular stress: a complex interplay affecting human health

Flavonoid consumption has beneficial effects on human health, however, clinical evidence remains often inconclusive due to high interindividual variability. Although this high interindividual variability has been consistently observed in flavonoid research, the potential underlying reasons are still poorly studied. Especially the knowledge on the impact of health status on flavonoid responsiveness is limited and merits more investigation. Here, we aim to highlight the bidirectional interplay between flavonoids and cellular stress. First, the state-of-the-art concerning inflammatory stress and mitochondrial dysfunction is reviewed and a comprehensive overview of recent in vitro studies investigating the impact of flavonoids on cellular stress, induced by tumor necrosis factor α, lipopolysaccharide and mitochondrial stressors, is given. Second, we critically discuss the influence of cellular stress on flavonoid uptake, accumulation, metabolism and cell responses, which has, to our knowledge, never been extensively reviewed before. Next, we advocate the innovative insight that stratification of the general population based on health status can reveal subpopulations that benefit more from flavonoid consumption. Finally, suggestions are given for the development of future cell models that simulate the physiological micro-environment, including interindividual variability, since more mechanistic research is needed to establish scientific-based personalized food recommendations for specific subpopulations.

Intracellular quercetin accumulation and its impact on mitochondrial dysfunction in intestinal Caco-2 cells

PURPOSE

Flavonoid bioavailability and bioactivity is associated with interindividual variability, which is partially due to differences in health status. Previously, it was demonstrated that cellular stress, especially mitochondrial stress, increases intracellular quercetin uptake and this is associated with beneficial health effects. Here, the impact of quercetin on mitochondrial dysfunction, induced by stressors targeting different sites of the electron transport chain, is investigated. The influence of the mitochondrial stress on quercetin uptake and subcellular location is studied and the accumulated quercetin metabolites in intestinal Caco-2 cells and mitochondria are characterized.

PRINCIPAL RESULTS

It was observed that quercetin counteracted (i) the carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone (FCCP)-induced decrease in maximum oxygen consumption, (ii) the valinomycin-, oligomycin- and FCCP-induced reactive oxygen species production and (iii) the valinomycin-induced disruption of mitochondrial membrane potential. Using confocal microscopy, it was found that upon mitochondrial stress, the intracellular quercetin accumulation increased and was partially located in the mitochondria. Finally, it was demonstrated that quercetin was present as O-methyl, O-methylglucuronide and O-methylsulfate conjugates in the cell lysate and mitochondria-enriched fraction.

MAJOR CONCLUSIONS

This study shows that quercetin can partially restore, especially FCCP-induced, mitochondrial dysfunction and this protective effect was linked with an intracellular quercetin accumulation in the mitochondria of intestinal cells.

Aldose reductase regulates doxorubicin-induced immune and inflammatory responses by activating mitochondrial biogenesis

We have recently demonstrated that aldose reductase (AR) inhibitor; fidarestat prevents doxorubicin (Dox)-induced cardiotoxic side effects and inflammation in vitro and in vivo. However, the effect of fidarestat and its combination with Dox on immune cell activation and the immunomodulatory effects are not known. In this study, we examined the immunomodulatory effects of fidarestat in combination with Dox in vivo and in vitro. We observed that fidarestat decreased Dox-induced upregulation of CD11b in THP-1 monocytes. Fidarestat further attenuated Dox-induced upregulation of IL-6, IL-1β, and Nos2 in murine BMDM. Fidarestat also attenuated Dox-induced activation and infiltration of multiple subsets of inflammatory immune cells identified by expression of markers CD11b+, CD11b+F4/80+, Ly6C+CCR2high, and Ly6C+CD11b+ in the mouse spleen and liver. Furthermore, significant upregulation of markers of mitochondrial biogenesis PGC-1α, COX IV, TFAM, and phosphorylation of AMPKα1 (Ser485) was observed in THP-1 cells and livers of mice treated with Dox in combination with fidarestat. Our results suggest that fidarestat by up-regulating mitochondrial biogenesis exerts protection against Dox-induced immune and inflammatory responses in vitro and in vivo, providing further evidence for developing fidarestat as a combination agent with anthracycline drugs to prevent chemotherapy-induced inflammation and toxicity.

Modulation of Human Sperm Mitochondrial Respiration Efficiency by Plant Polyphenols

Plant bioactives, such as polyphenols, can differentially affect (positively or negatively) sperm quality, depending on their concentration. These molecules have been proposed as natural scavengers of reactive oxygen species (ROS) for male infertility treatment. However, few data are available about their effects on the molecular mechanisms related to sperm quality and, in particular, to sperm mitochondrial function. We investigated the effects of quercetin, naringenin, genistein, apigenin, luteolin, and resveratrol at the concentration of 0.1-1000 nM on mitochondrial respiration efficiency. Upon chemical exposure, spermatozoa were swollen in a hypotonic solution and used for polarographic assays of mitochondrial respiration. All tested compounds, except for apigenin, caused a significant increase in the mitochondrial respiration efficiency at the concentration of 0.1 nM, and a significant decrease starting from concentrations of 10 nM. The analysis of oxygen consumption rate in the active and in the resting state of mitochondrial respiration suggested different mechanisms by which the tested compounds modulate mitochondrial function. Therefore, by virtue of their ability to stimulate the respiration active state, quercetin, genistein, and luteolin were found to improve mitochondrial function in asthenozoospermic samples. Our results are relevant to the debate on the promises and perils of natural antioxidants in nutraceutical supplementation.

Novel nano-pomegranates based on astragalus polysaccharides for targeting ERα-positive breast cancer and multidrug resistance

Chemotherapy is an important method for treating breast cancer. However, multidrug resistance is one of the major challenges in breast cancer chemotherapy. There is an urgent need to develop novel, effective antitumor strategies that will perfect existing therapeutic regimens. In this study, the double-targeted nanocarrier, Quercetin-3'3-dithiodipropionic acid-Astragalus polysaccharides-Folic acid (QDAF), was successfully synthesized and self-assembled into a neoteric nano-targeted delivery strategy, named nano-pomegranates, and which were utilized to effectively inhibit multidrug resistance in estrogen receptor α (ERα)-positive breast tumor. The outstanding abilities of nano-pomegranates to release the drug in a reducing environment was determined by in vitro release assay. The cellular studies in MCF-7 cells were examined that nano-pomegranates have remarkable efficiencies of enhancing cellular uptake, inhibition and necrosis and apoptosis. In vivo antitumor experiments showed that nano-pomegranates have better anti-tumor effects and lower systemic toxicity than free Cur. In conclusion, nano-pomegranates have great potential in anti-breast cancer treatment.

Epigenetic mechanisms underlying the benefits of flavonoids in cardiovascular health and diseases: are long non-coding RNAs rising stars?

Cardiovascular diseases (CVDs) rank as the first leading cause of death globally. High dietary polyphenol (especially flavonoids) intake has strongly been associated with low incidence of the primary outcome, overall mortality, blood pressure, inflammatory biomarkers, onset of new-onset type 2 diabetes mellitus (T2DM), and obesity. Phytogenic flavonoids affect the physiological and pathological processes of CVDs by modulating various biochemical signaling pathways. Non-coding RNAs (ncRNAs) have attracted increasing attention as fundamental regulator of gene expression involved in CVDs. Among the different ncRNA subgroups, long ncRNAs (lncRNAs) have recently emerged as regulatory eukaryotic transcripts and therapeutic targets with important and diverse functions in health and diseases. lncRNAs may be associated with the initiation, development and progression of CVDs by modulating acute and chronic inflammation, adipogenesis and lipid metabolism, and cellular physiology. This review summarizes this research on the modulatory effects of lncRNAs and their roles in mediating cellular processes. The mechanisms of action of flavonoids underlying their therapeutic effects on CVDs are also discussed. Based on our review, flavonoids might facilitate a significant epigenetic modification as part (if not full) of their tissue-/cell-related biological effects. This finding may be attributed to their interaction with cellular signaling pathways involved in chronic diseases. Certain lncRNAs might be the target of specific flavonoids, and some critical signaling processes involved in the intervention of CVDs might mediate the therapeutic roles of flavonoids.

An Overview of the Mechanism of Penthorum chinense Pursh on Alcoholic Fatty Liver

Alcohol liver disease (ALD) caused by excessive alcohol consumption is a progressive disease, and alcohol fatty liver disease is the primary stage. Currently, there is no approved drug for its treatment. Abstinence is the best way to heal, but patients' compliance is poor. Unlike other chronic diseases, alcohol fatty liver disease is not caused by nutritional deficiencies; it is caused by the molecular action of ingested alcohol and its metabolites. More and more studies have shown the potential of Penthorum chinense Pursh (PCP) in the clinical use of alcohol fatty liver treatment. The purpose of this paper is to reveal from the essence of PCP treatment of alcohol liver mechanism mainly by the ethanol dehydrogenase (ADH) and microsomal ethanol oxidation system-dependent cytochrome P4502E1 (CYP2E1) to exert antilipogenesis, antioxidant, anti-inflammatory, antiapoptotic, and autophagy effects, with special emphasis on its mechanisms related to SIRT1/AMPK, KEAP-1/Nrf2, and TLR4/NF-κB. Overall, data from the literature shows that PCP appears to be a promising hepatoprotective traditional Chinese medicine (TCM).

Remedying the Mitochondria to Cure Human Diseases by Natural Products

Mitochondria are the ‘engine' of cells. Mitochondrial dysfunction is an important mechanism in many human diseases. Many natural products could remedy the mitochondria to alleviate mitochondria-involved diseases. In this review, we summarized the current knowledge of the relationship between the mitochondria and human diseases and the regulation of natural products to the mitochondria. We proposed that the development of mitochondrial regulators/nutrients from natural products to remedy mitochondrial dysfunction represents an attractive strategy for a mitochondria-involved disorder therapy. Moreover, investigating the mitochondrial regulation of natural products can potentiate the in-depth comprehension of the mechanism of action of natural products.

MicroRNA-based regulatory mechanisms underlying the synergistic antioxidant action of quercetin and catechin in H2O2-stimulated HepG2 cells: Roles of BACH1 in Nrf2-dependent pathways

The microRNA-based mechanisms underlying the antioxidant action(s) of co-existing flavonoids in response to oxidative stress are of high interest. This study aimed to extend the existing knowledge and provide insights into the potential regulatory network in response to oxidative stress and the co-presence of quercetin and catechin antioxidants, via a preclinical approach using H₂O₂-stimulated HepG2 cells. It was confirmed that BACH1 serves as an essential and direct negative regulator of the Keap1-Nrf2 signaling pathway and the antioxidant synergism between quercetin and catechin. BACH1 promoted reactive oxygen species (ROS) accumulation while inhibiting cell growth, which could be reversed by the synergistic action of let-7a-5p and miR-25-3p in the co-presence of quercetin and catechin. Both let-7a-5p and miR-25-3p could directly regulate the expression and function of BACH1 (e.g. upregulation of the two miRNAs could rescue largely overexpression of BACH1). Although these molecular interactions likely represented only some aspects of the overall regulatory network, this research confirms the feasibility of the combined uses of dietary flavonoids with chemopreventive properties in synergy during multiple-target interactions and multiple-pathway regulation.

Interplay between NADH oxidation by complex I, glutathione redox state and sirtuin-3, and its role in the development of insulin resistance

Metabolic diseases are characterized by high NADH/NAD⁺ ratios due to excessive electron supply, causing defective mitochondrial function and impaired sirtuin-3 (SIRT-3) activity, the latter driving to oxidative stress and altered fatty acid β-oxidation. NADH is oxidized by the complex I in the electron transport chain, thereby factors inhibiting complex I like acetylation, cardiolipin peroxidation, and glutathionylation by low GSH/GSSG ratios affects SIRT3 function by increasing the NADH/NAD⁺ ratio. In this review, we summarized the evidence supporting a role of the above events in the development of insulin resistance, which is relevant in the pathogenesis of obesity and diabetes. We propose that maintenance of proper NADH/NAD⁺ and GSH/GSSG ratios are central to ameliorate insulin resistance, as alterations in these redox couples lead to complex I dysfunction, disruption of SIRT-3 activity, ROS production and impaired β-oxidation, the latter two being key effectors of insulin resistance.

Molecular mechanisms linking environmental toxicants to cancer development: Significance for protective interventions with polyphenols

Human exposure to environmental toxicants with diverse mechanisms of action is a growing concern. In addition to well-recognized carcinogens, various chemicals in environmental and occupational settings have been suggested to impact health, increasing susceptibility to cancer by inducing genetic and epigenetic changes. Accordingly, in this review, we have discussed recent insights into the pathological mechanisms of these chemicals, namely their effects on cell redox and calcium homeostasis, mitochondria and inflammatory signaling, with a focus on the possible implications for multi-stage carcinogenesis and its reversal by polyphenols. Plant-derived polyphenols, such as epigallocatechin-gallate, resveratrol, curcumin and anthocyanins reduce the incidence of cancer and can be useful nutraceuticals for alleviating the detrimental outcomes of harmful pollutants. However, development of therapies based on polyphenol administration requires further studies to validate the biological efficacy, identifying effective doses, mode of action and new delivery forms. Innovative microphysiological testing models are presented and specific proposals for future trials are given. Merging the current knowledge of multifactorial actions of specific polyphenols and chief environmental toxicants, this work aims to potentiate the delivery of phytochemical-based protective treatments to individuals at high-risk due to environmental exposure.

Effects of quercetin on cadmium-induced toxicity in rat urine using metabonomics techniques

This study aimed to analyse the protective effects of quercetin on the toxicity of cadmium (Cd) using metabonomics techniques. Sixty male Sprague-Dawley rats were randomly divided into six groups (n = 10): control group (C), low-dose quercetin-treated group (Q1; 10 mg/kg bw/day), high-dose quercetin-treated group (Q2; 50 mg/kg bw/day), Cd-treated group (D; 4.89 mg/kg bw/day), low-dose quercetin plus Cd-treated group (DQ1) and high-dose quercetin plus Cd-treated group (DQ2). The rats continuously received quercetin and Cd via gavage and drinking water for 12 weeks, respectively. The rat urine samples were collected for metabonomics analysis. Finally, 10 metabolites were identified via the metabonomics profiles of the rat urine samples. Compared with the control group, the intensities of taurine, phosphocreatine, l-carnitine and uric acid were significantly decreased (p < 0.01) and those of LysoPC (18: 2 (9Z, 12Z)), guanidinosuccinic acid, dopamine, 2,5,7,8-tetramethyl-2(2'-carboxyethyl)-6-hydroxychroman and allantoic acid were significantly increased (p < 0.01) in the Cd-treated group. However, the intensities of the aforementioned metabolites had restorative changes in the high-dose quercetin plus Cd-treated groups unlike those in Cd-treated group (p < 0.01 or p < 0.05). Results indicated that quercetin exerts protective effects on Cd-induced toxicity by regulating energy and lipid metabolism, enhancing the antioxidant defence system and protecting liver and kidney function and so on.

Antitumor Effects of Quercetin in Hepatocarcinoma In Vitro and In Vivo Models: A Systematic Review

Quercetin is a flavonoid present in fruits, vegetables and plants with antioxidant, anti-inflammatory and anticancer properties. Its beneficial activities have been demonstrated in different human pathologies, including hepatoprotective effects against liver disorders. High mortality and late diagnosis of the primary liver tumor hepatocarcinoma (HCC) makes this cancer an interesting target for the study of quercetin effects. Our aim was to systematically review antitumor activities of quercetin in HCC preclinical studies employing single, encapsulated, combined or derived quercetin forms. Literature search was conducted in PubMed, Scopus and Web of Science (WOS), and 39 studies were finally included. We found that 17 articles evaluated quercetin effects alone, six used encapsulated strategy, 10 combined this flavonoid, two decided to co-encapsulate it and only four studied effects of quercetin derivatives, highlighting that only nine included in vivo models. Results evidence the quercetin antiproliferative and proapoptotic properties against HCC either alone and with the mentioned strategies; nevertheless, few investigations assessed specific activities on different processes related with cancer progression. Overall, further studies including animal models are needed to deeper investigate the precise mechanisms of action of quercetin as antitumor agent, as well as the potential of novel strategies aimed to improve quercetin effects in HCC.

Long non-coding RNA CRNDE enhances cervical cancer progression by suppressing PUMA expression

Cervical cancer is the second most common gynecological malignancy, and it remains a leading cause of tumor-related death among female in the world. Long non-coding RNAs (lncRNAs) have been indicated to play essential roles in tumorigenesis, and the lncRNA colorectal neoplasia differentially expressed (CRNDE) is increased in several tumors. Nevertheless, little is known about the effects of lncRNA CRNDE on human cervical cancer. The aim of the study was to explore the clinical significance of lncRNA CRNDE expression in human cervical cancer. Our results indicated that CRNDE expression was increased in cervical cancer tissues and several cervical cancer cell lines. Through loss-of-function and gain-of-function approaches, we found that CRNDE knockdown markedly reduced cervical cancer cell proliferation, while CRNDE overexpression significantly promoted cervical cancer cell growth. Consistently, CRNDE decreasing obviously inhibited tumorigenicity of cervical cancer cells in vivo, whereas CRNDE increasing markedly promoted cervical cancer progression. Mechanistically, we verified that CRNDE bond to p53 upregulated modulator of apoptosis (PUMA), and PUMA was required for CRNDE to enhance cervical cancer cell growth. Our study demonstrated that CRNDE, combined with PUMA, could be utilized as factor for the clinical diagnosis and prognosis of cervical cancer, and might be potential target for developing effective therapeutic strategy to prevent cervical cancer progression.

Taurine rescues the arsenic-induced injury in the pancreas of rat offsprings and in the INS-1 cells

Arsenic was an established carcinogen and toxicant, occurring in drinking water and food. Arsenic was increasingly being blamed as a risk factor for diabetes mellitus. Recent studies have found that arsenic could induce the generation of reactive oxygen species (ROS) and mitochondria were the major targets of ROS. Damage mitochondria could be removed by mitophagy and mitophagy played a defensive role against cellular apoptosis. To investigate whether the arsenic could induce the injury in mitochondria, we treated Wistar rat offsprings and INS-1 cells with As2O3 and sodium arsenite, respectively. Our results showed that arsenic induced the generation of ROS in both rat offsprings' pancreas and INS-1 cells. The generation of ROS induced by arsenic could inhibit the expression of PPARγ. PPARγ is a major impact on mitochondrial function. The inhibition of PPARγ induced the reduction of PINK1 signaling and the upregulation of Bax. PINK1 signaling was one of the classical pathways of mitophagy. The inhibition of mitophagy induced the activation of apoptosis both in rat offsprings' pancreas and INS-1 cells. After treated with Rosiglitazone (RGS, PPARγ receptor agonist), PPARγ was rescued, the expression of PINK1 significantly increasing and the apoptosis was restrained. We used Taurine (Tau) as the protective agent both in rat offsprings' pancreas and INS-1 cells, after treated with Tau, the production of ROS was decreased significantly and the downgrade of PPARγ was rescued.