Andrographolide sodium bisulfate-induced apoptosis and autophagy in human proximal tubular endothelial cells is a ROS-mediated pathway

Molecular mechanisms of andrographolide-induced kidney injury and senescence via SIRT3 inhibition

Andrographolide, a diterpene compound derived from the medicinal plant Andrographis paniculata, possesses anti-inflammatory, antioxidant, antitumor, and antiviral properties. Injectable formulations containing andrographolide, such as Potassium Sodium Dehydroandrographolide Succinate for Injection (PSDS), are widely used in clinical practice to treat various diseases, including upper respiratory tract infections. However, clinical reports have highlighted that andrographolide-based herbal injections may induce acute kidney injury and other renal adverse effects, thereby restricting its clinical application. Despite these concerns, the molecular mechanisms underlying andrographolide-induced nephrotoxicity remain poorly understood. In this study, we demonstrated that andrographolide induces inflammation and fibrosis in renal tubular epithelial cells and mouse kidneys. Notably, we identified for the first time that andrographolide promotes cellular senescence in renal tubular epithelial cells and mouse kidneys while downregulating the expression and enzymatic activity of SIRT3. Mechanistic investigations revealed that andrographolide mediates kidney injury and senescence through inhibition of the SIRT3/p53 signaling pathway. Furthermore, andrographolide was found to disrupt the interaction between SIRT3 and p53, resulting in increased acetylation of p53 and upregulation of its downstream target genes involved in inflammation, fibrosis, and senescence. These findings elucidate the molecular mechanisms of andrographolide-induced nephrotoxicity and provide a scientific basis for developing strategies to reduce its toxic effects.

The roles of TRPC6 in renal tubular disorders: a narrative review

The transient receptor potential canonical 6 (TRPC6) channel, a nonselective cation channel that allows the passage of Ca2+, plays an important role in renal diseases. TRPC6 is activated by Ca2+ influx, oxidative stress, and mechanical stress. Studies have shown that in addition to glomerular diseases, TRPC6 can contribute to renal tubular disorders, such as acute kidney injury, renal interstitial fibrosis, and renal cell carcinoma (RCC). However, the tubule-specific physiological functions of TRPC6 have not yet been elucidated. Its pathophysiological role in ischemia/reperfusion (I/R) injury is debatable. Thus, TRPC6 may have dual roles in I/R injury. TRPC6 induces renal fibrosis and immune cell infiltration in a unilateral ureteral obstruction (UUO) mouse model. Additionally, TRPC6 overexpression may modify G2 phase transition, thus altering the DNA damage checkpoint, which can cause genomic instability and RCC tumorigenesis and can control the proliferation of RCC cells. This review highlights the importance of TRPC6 in various conditions of the renal tubular system. To better understand certain renal disorders and ultimately identify new therapeutic targets to improve patient care, the pathophysiology of TRPC6 must be clarified.

Anti-Cancer Agent: The Labdane Diterpenoid-Andrographolide

In spite of the progress in treatment strategies, cancer remains a major cause of death worldwide. Therefore, the main challenge should be the early diagnosis of cancer and the design of an optimal therapeutic strategy to increase the patient's life expectancy as well as the continuation of the search for increasingly active and selective molecules for the treatment of different forms of cancer. In the recent decades, research in the field of natural compounds has increasingly shifted towards advanced and molecular level understandings, thus leading to the development of potent anti-cancer agents. Among them is the diterpene lactone andrographolide, isolated from Andrographis paniculata (Burm.f.) Wall. ex Nees that showed shows a plethora of biological activities, including not only anti-cancer activity, but also anti-inflammatory, anti-viral, anti-bacterial, neuroprotective, hepatoprotective, hypoglycemic, and immunomodulatory properties. Andrographolide has been shown to act as an anti-tumor drug by affecting specific molecular targets that play a part in the development and progression of several cancer types including breast, lung, colon, renal, and cervical cancer, as well as leukemia and hepatocarcinoma. This review comprehensively and systematically summarized the current research on the potential anti-cancer properties of andrographolide highlighting its mechanisms of action, pharmacokinetics, and potential side effects and discussing the future perspectives, challenges, and limitations of use.

Nephrotoxicity induced by natural compounds from herbal medicines - a challenge for clinical application

Herbal medicines (HMs) have long been considered safe and effective without serious toxic and side effects. With the continuous use of HMs, more and more attention has been paid to adverse reactions and toxic events, especially the nephrotoxicity caused by natural compounds in HMs. The composition of HMs is complex and various, especially the mechanism of toxic components has been a difficult and hot topic. This review comprehensively summarizes the kidney toxicity characterization and mechanism of nephrotoxic natural compounds (organic acids, alkaloids, glycosides, terpenoids, phenylpropanoids, flavonoids, anthraquinones, cytotoxic proteins, and minerals) from different sources. Recommendations for the prevention and treatment of HMs-induced kidney injury were provided. In vitro and in vivo models for evaluating nephrotoxicity and the latest biomarkers are also included in this investigation. More broadly, this review may provide theoretical basis for safety evaluation and further comprehensive development and utilization of HMs in the future.

Andrographolide, a natural anti-inflammatory agent: An Update

Botanicals have attracted much attention in the field of anti-inflammatory due to their good pharmacological activity and efficacy. Andrographis paniculata is a natural plant ingredient that is widely used around the world. Andrographolide is the main active ingredient derived from Andrographis paniculata, which has a good effect on the treatment of inflammatory diseases. This article reviews the application, anti-inflammatory mechanism and molecular targets of andrographolide in different inflammatory diseases, including respiratory, digestive, immune, nervous, cardiovascular, skeletal, and tumor system diseases. And describe its toxicity and explain its safety. Studies have shown that andrographolide can be used to treat inflammatory lesions of various systemic diseases. In particular, it acts on many inflammation-related signalling pathways. The future direction of andrographolide research is also introduced, as is the recent research that indicates its potential clinical application as an anti-inflammatory agent.

Isoandrographolide from Andrographis paniculata ameliorates tubulointerstitial fibrosis in ureteral obstruction-induced mice, associated with negatively regulating AKT/GSK-3β/β-cat signaling pathway

Tubulointerstitial fibrosis (TIF) is a prominent pathological manifestation for the progression of almost all chronic kidney diseases (CKDs) to end-stage renal failure. However, there exist few efficient therapies to cure TIF. Our recent results showed that (8R, 12S)-isoandrographolide (ISA), a diterpenoid lactone ingredient of traditional Chinese herbal Andrographis paniculata (Burm.f.) Nees, exhibited anti-pulmonary fibrosis in silica-induced mice. Herein, we investigated the therapeutic effect of ISA on TIF, using mice subjected to unilateral ureteral obstruction (UUO) and human kidney proximal tubular epithelial (HK-2) cells treated with transforming growth factor-β1 (TGF-β1) or tumor necrosis factor-α (TNF-α). The pathological changes and collagen deposition results displayed that ISA administration significantly attenuated inflammatory response, ameliorated TIF, and protected the kidney injury. Interestingly, ISA revealed much lower cytotoxicity on HK-2 cells, but exhibited stronger inhibitory effect on tubular epithelial mesenchymal transformation (EMT) and inflammation, as compared to andrographolide (AD), the major ingredient of A. paniculata extract that has been reported to ameliorate TIF in diabetic nephropathy mice. It was further clarified that the amelioration of TIF by ISA was associated with suppressing the aberrant activation of AKT/GSK-3β/β-catenin pathway through network pharmacology analysis and experimental validation. Taken together, these findings indicate that ISA is a promising lead compound for development of anti-TIF, and even broad-spectrum anti-fibrotic drugs.

Neuroprotective potential of berberine in modulating Alzheimer's disease via multiple signaling pathways

Berberine is one of the most important quinoline alkaloids, which has shown numerous pharmacological activities. There are pieces of evidence that berberine serves as a promising substance for treating Alzheimer's disease (AD). Recently, numerous studies on animal models have shown the neuroprotective role of berberine. AD is a complex disease having multiple pathological factors. Berberine restrains the deposition of amyloid plaques and neurofibrillary tangles. Substantial studies have demonstrated that berberine may also exhibit the protective effect against the risk factors associated with AD. This review illustrates the role of berberine in neuroinflammation, oxidative stress and its activity against acetylcholinesterase enzyme. It also focuses on the bioavailability and safety of berberine in AD. However, more investigations are required to explore the bioavailability and safety assessment of berberine and its new perspectives in limiting the AD-related pathogenesis and risk factors. PRACTICAL APPLICATIONS: Current therapeutic measures only provide symptomatic relief against AD by slowing memory loss, resolving thinking problems and behavioral issues. In recent past years, many biological actions and potential therapeutic applications have been observed by berberine particularly in neurological diseases. Berberine has been investigated by various researchers for its activity against AD. This review demonstrates a variety of mechanisms by which berberine imparts its neuroprotective roles and provides the possible mechanism of action of berberine by which it prevents the formation of neurofibrillary tangles and disaggregation of amyloid beta plaques in AD. It also focuses that berberine limits the neuroinflammation and oxidative stress in AD. Pre-clinical aspects of berberine against AD are also discussed. Eventually, a prospect is formulated that berberine might be a therapeutically significant agent for treating and preventing AD.

Andrographolide as a potent and promising antiviral agent

Andrographolide is a labdane diterpenoid extracted and purified from the aerial parts of plants belonging to genus Andrographis (Acanthaceae). The research has shown the plant based compound is low cytotoxic, having antimicrobial, anti-cancer, antiviral and anti-parasitic effects. Andrographolide both prevent spread as well as transmission of virus to neighboring cells by interfering with different cell signaling pathways. In addition to its medicinal value, plant has been found having nutritional value. Therefore being cost effective, easy availability and having nutritional value as a natural supplement, can be used to improve the quality of life in countries having low standard of living. Due to the limited number of effective vaccines, the plant-based antiviral drugs have provided considerable hope for fighting against the viral infections. The plant-derived compound when produced in large quantities is cost effective with low cytotoxic effects. However, much deep insight research at the molecular level is needed to develop the molecules against the viral infection. This paper aims to highlight the antiviral role of Andrographolide that can made significant contributions toward the improvement of human health and will also summarize the current status and future strategies concerning the therapeutic applications of Andrographolide to combat different viral disease in humans.

Andrographis paniculata (Burm. F) Wall ex Nees: Antiviral properties

Andrographis paniculata is home to a rich variety of molecules especially andrographolide and its derivatives. Clinical properties of the andrographolide are multifarious and include: analgesic, antipyretic, antiretroviral, antiproliferative, antimalarial, antithrombotic, antihyperglycemic, antiurolethial, antilesihmaniasis, hepatoprotective, immune-modulatory, protective against alcohol induced toxicity and cardioproetcive activity and anticancer activity. Andrographolide, neoandrographolide, dehydroandrographolide and several natural and synthetic derivatives of it: 14-deoxy-11,12-didehydroandrographolide and 14-deoxyandrographolide, dehydroandrographolide succinic acid monoester (DAMS), 14-ά-lipoyl andrographolide (AL-1), 14-acetyl-3,9-isopropyl-ideneandrographolide, 14-acetylandrographolide, 3,14,19-triacetylandrographolide, and 3,9-isopropyl-idene andrographolide, are shown to possess significant antiviral activity against HIV, influenza A, HBV, HCV, HPP and HSV. Studies on SARS CoV 2 is restricted to in silico molecular docking studies on viral targets and selected host target proteins. The main targets of andrographolide and its derivatives are fusion and adsorption of virus to the host cell, binding to viral receptor and co-receptor, enzymes involved in DNA/RNA/Genome replication by the virus, translation, post-translation and reverse transcription. Andrographolide as a drug is yet to reach its full therapeutic potential since this molecule shows low bioavailability. Andrographolide therapy is in need of an appropriate delivery system that may increase its bioavailability. Further high-quality studies are needed to firmly establish the clinical efficacy of the plant.

Dihydroartemisinin induces pyroptosis by promoting the AIM2/caspase-3/DFNA5 axis in breast cancer cells

BACKGROUND

Breast cancer is a complex disease. Recent research has examined the anticancer effects of dihydroartemisinin (DHA) on breast cancer. However, the molecular mechanism of the antitumour effect of DHA is unclear.

METHODS

MCF-7 and MDA-MB-231 cell lines were used for in vitro research. BALB/c nude mice were used to establish breast cancer xenografts. The mRNA and protein levels were analysed by qRT-PCR and western blotting, respectively. Flow cytometry was performed to examine cell apoptosis. ELISA kits were used to evaluate the production of interleukin-1β (IL-1β) and IL-18. LDH and ATP release were individually measured with the corresponding kits. A colony formation assay was used to examine the proliferation of breast cancer cells.

RESULTS

DHA inhibited proliferation and induced pyroptosis in breast cancer cells. Mechanistically, DHA activated the expression of absent in melanoma 2 (AIM2), caspase-3 and gasdermin E (DFNA5). In addition, AIM2 promoted DFNA5 expression by activating caspase-3. Knockdown of AIM2 and DFNA5 significantly enhanced breast cancer cell resistance to DHA. In vivo experiments showed that the tumorigenicity of breast cancer cells was significantly suppressed by DHA. Moreover, the AIM2/caspase-3/DFNA5 axis was activated by DHA and then induced pyroptosis.

CONCLUSIONS

Our findings indicate that DHA inhibits tumorigenesis by inducing pyroptosis in breast cancer cells, highlighting a promising therapeutic strategy for breast cancer.

Andrographolide and Its 14-Aryloxy Analogues Inhibit Zika and Dengue Virus Infection

Andrographolide is a labdene diterpenoid with potential applications against a number of viruses, including the mosquito-transmitted dengue virus (DENV). In this study, we evaluated the anti-viral activity of three 14-aryloxy analogues (ZAD-1 to ZAD-3) of andrographolide against Zika virus (ZIKV) and DENV. Interestingly, one analogue, ZAD-1, showed better activity against both ZIKV and DENV than the parental andrographolide. A two-dimension (2D) proteomic analysis of human A549 cells treated with ZAD-1 compared to cells treated with andrographolide identified four differentially expressed proteins (heat shock 70 kDa protein 1 (HSPA1A), phosphoglycerate kinase 1 (PGK1), transketolase (TKT) and GTP-binding nuclear protein Ran (Ran)). Western blot analysis confirmed that ZAD-1 treatment downregulated expression of HSPA1A and upregulated expression of PGK1 as compared to andrographolide treatment. These results suggest that 14-aryloxy analogues of andrographolide have the potential for further development as anti-DENV and anti-ZIKV agents.

Synthesis, extracorporeal nephrotoxicity, and 3D-QSAR of andrographolide derivatives

Andrographolide is a traditional Chinese medicine monomer with many pharmacological activities, but has potential nephrotoxicity. Here, we aim to investigate the relationship between modification of andrographolide structure and its nephrotoxicity. Twenty-three andrographolide derivatives were synthesized, and their structures were confirmed by ¹ H-NMR and HRMS. Nephrotoxicity of these compounds against human renal tubular epithelial (HK-2) cells was evaluated using the MTT assay. The results indicated that most of them had significantly reduced nephrotoxicity, especially compounds III, V, and IX_c , with IC₅₀ values of 1,985, 1,300, and 806.9 μmol/L, respectively, which were obviously superior to andrographolide (IC₅₀ 30.60 μmol/L). However, compounds I_a -I_f (IC₅₀ values < 30 μmol/L), the 14-OH derivatives of andrographolide, showed higher nephrotoxicity than that of andrographolide. Three-dimensional quantitative structure-activity relationship (3D-QSAR) models of COMFA and COMSIA were established (COMFA: q²  = 0.639, r²  = 0.951; COMSIA: q²  = 0.569, r²  = 0.857). This model allowed proposing five new compounds with lower theoretical nephrotoxicity, which would be worthwhile to synthesize and evaluate. We believe that predicted models will help us to understand the structural modification requirements of andrographolide to reduce the nephrotoxicity, and further investigations will be needed to determine the mechanism involved in the effect of less nephrotoxic compounds.

Andrographolide sodium bisulfate attenuates UV‑induced photo‑damage by activating the keap1/Nrf2 pathway and downregulating the NF‑κB pathway in HaCaT keratinocytes

Oxidative and inflammatory damage has been suggested to play important roles in the pathogenesis of skin photoaging. Andrographolide sodium bisulfate (ASB) is a soluble derivative of andrographolide and has known antioxidant and anti‑inflammatory properties. In the present study, cellular experiments were designed to investigate the molecular mechanisms underlying the effect of ASB in relieving ultraviolet (UV)‑induced photo‑damage. Following ASB pretreatment and UV irradiation, the apoptosis and necrosis of HaCaT cells were investigated by Hoechst 33342/propidium iodide staining. Reactive oxygen species (ROS) production was investigated using a DCFH‑DA fluorescence probe. Furthermore, the protein expression levels of p65, NF‑κB inhibitor‑α, nuclear factor E2‑related factor 2 (Nrf2) and kelch‑like ECH‑associated protein 1 (keap1) were measured via western blotting and immunofluorescence analyses. Furthermore, NF‑κB‑mediated cytokines were assessed by ELISA, and Nrf2‑mediated genes were detected by reverse transcription‑quantitative PCR. Pretreatment with ASB markedly increased cell viability, decreased cell apoptosis and decreased UV‑induced excess ROS levels. In addition, ASB activated the production of Nrf2 and increased the mRNA expression levels of glutamate‑cysteine ligase catalytic subunit and NAD(P)H quinone oxidoreductase 1, while ASB downregulated the protein expression of p65 and decreased the production of interleukin (IL)‑1β, IL‑6 and tumor necrosis factor‑α. These results suggested that ASB attenuates UV‑induced photo‑damage by activating the keap1/Nrf2 pathway and downregulating the NF‑κB pathway in HaCaT keratinocytes.

A proteomic analysis of the anti-dengue virus activity of andrographolide

Andrographolide is a major bioactive constituent of Andrographis paniculata that has been shown in vitro to have antiviral activity against a number of viruses, including the mosquito transmitted dengue virus (DENV). However, how andrographolide exerts an anti-DENV effect remains unclear. This study therefore sought to further understand the mechanism of action of andrographolide in inhibiting DENV infection of liver cells using a proteomic based approach. Both 1 dimension (D) and 2D proteome systems were used. Initial data was generated through andrographolide treatment of HepG2 cells without DENV infection (1D analysis), while subsequent data was generated through a combination of andrographolide treatment and DENV infection (2D analysis). A total of 17 (1D) and 18 (2D) proteins were identified as differentially regulated. The analyses identified proteins involved in chaperone activities, as well as energy production. In particular evidence suggested an important role for GRP78 and the unfolded protein response in mediating the anti-DENV activity of andrographolide, which might, in part, explain the broad antiviral activity of andrographolide.

Nanostructured Dihydroartemisinin Plus Epirubicin Liposomes Enhance Treatment Efficacy of Breast Cancer by Inducing Autophagy and Apoptosis

The heterogeneity of breast cancer and the development of drug resistance are the relapse reasons of disease after chemotherapy. To address this issue, a combined therapeutic strategy was developed by building the nanostructured dihydroartemisinin plus epirubicin liposomes. Investigations were performed on human breast cancer cells in vitro and xenografts in nude mice. The results indicated that dihydroartemisinin could significantly enhance the efficacy of epirubicin in killing different breast cancer cells in vitro and in vivo. We found that the combined use of dihydroartemisinin with epirubicin could efficiently inhibit the activity of Bcl-2, facilitate release of Beclin 1, and further activate Bax. Besides, Bax activated apoptosis which led to the type I programmed death of breast cancer cells while Beclin 1 initiated the excessive autophagy that resulted in the type II programmed death of breast cancer cells. In addition, the nanostructured dihydroartemisinin plus epirubicin liposomes prolonged circulation of drugs, and were beneficial for simultaneously delivering drugs into breast cancer tissues. Hence, the nanostructured dihydroartemisinin plus epirubicin liposomes could provide a new therapeutic strategy for treatment of breast cancer.

Andrographolide, a diterpene lactone from Andrographis paniculata and its therapeutic promises in cancer

The diterpene lactone andrographolide, isolated from Andrographis paniculata, has been proven to possess several important protective biological activities, including antioxidant, anti-inflammatory, immunomodulatory, antiseptic, antimicrobial, cytotoxic, hypolipidemic, cardioprotective, hepatoprotective, and neuroprotective effects. In addition, it has been reported to play a therapeutic role in the treatment of major human diseases, such as Parkinson's disease, rheumatoid arthritis, and colitis. This systematic review aims to highlight andrographolide as a promising agent in cancer treatment. To this purpose, a number of databases were used to search for the cytotoxic/anticancer effects of andrographolide in pre-clinical and clinical studies. Among 1703 identified literature articles, 139 were included in this review; 109 were investigated as non-clinical, whereas 24, 3, and 3 were pre-clinical, clinical, and non-pre-clinical trials, respectively. Among the model systems, cultured cell lines appeared as the most frequently (79.14%) used, followed by in vivo models using rodents, among others. Furthermore, andrographolide was found to exert cytotoxic/anticancer effects on almost all types of cell lines with the underlying mechanisms involving oxidative stress, cell cycle arrest, anti-inflammatory and immune system mediated effects, apoptosis, necrosis, autophagy, inhibition of cell adhesion, proliferation, migration, invasion, anti-angiogenic activity, and other miscellaneous actions. After careful consideration of the relevant evidence, we suggest that andrographolide can be one of the potential agents in the treatment of cancer in the near future.

Increased reactive oxygen species levels cause ER stress and cytotoxicity in andrographolide treated colon cancer cells

Chemotherapy continues to play an essential role in the management of many cancers including colon cancer, the third leading cause of death due to cancer in the United States. Many naturally occurring plant compounds have been demonstrated to possess anti-cancer cell activity and have the potential to supplement existing chemotherapy strategies. The plant metabolite andrographolide induces cell death in cancer cells and apoptosis is dependent upon the induction of endoplasmic reticulum stress (ER stress) leading to the unfolded protein response (UPR). The goal of the present study was to determine the mechanism by which andrographolide induces ER stress and to further evaluate its role in promoting cell death pathways. The T84 and COLO 205 cancer cell lines were used to demonstrate that andrographolide induces increased ROS levels, corresponding anti-oxidant response molecules, and reduced mitochondrial membrane potential. No increases in ROS levels were detected in control colon fibroblast cells. Andrographolide-induced cell death, UPR signaling, and CHOP, Bax, and caspase 3 apoptosis elements were all inhibited in the presence of the ROS scavenger NAC. Additionally, andrographolide-induced suppression of cyclins B1 and D1 were also reversed in the presence of NAC. Finally, Akt phosphorylation and phospho-mTOR levels that are normally suppressed by andrographolide were also expressed at normal levels in the absence of ROS. These data demonstrate that andrographolide induces ER stress leading to apoptosis through the induction of ROS and that elevated ROS also play an important role in down-regulating cell cycle progression and cell survival pathways as well.

Alisol A 24-Acetate and Alisol B 23-Acetate Induced Autophagy Mediates Apoptosis and Nephrotoxicity in Human Renal Proximal Tubular Cells

Two natural compounds alisol A 24-acetate (24A) and alisol B 23-acetate (23B) are abundant in Rhizoma alismatis. In the present study, we evaluated the induction of 24A and 23B on apoptosis and possible nephrotoxicity of human renal proximal tubular (HK-2) cells by activating autophagy and also explored its regulation on PI3K/Akt/mTOR signaling pathway. Presently, Clusterin, Kim-1, and TFF-3 were considered to be new bioindicators of nephrotoxicity. Interestingly, the protein expression and mRNA levels of Clusterin, Kim-1 and TFF-3 could be significantly increased by 23B and 24A in vivo and in vitro. Furthermore, cell apoptosis could be triggered by 23B and 24A via significantly decreasing the protein expression and mRNA levels of Bcl-2 and Bcl-xl. Autophagy of HK-2 cells could be induced by both 23B and 24A via significantly enhancing the ratio of LC3II/LC3I, the protein expression of Beclin-1 as well as the mRNA levels of LC3 and Beclin-1. Meanwhile, PI3K/Akt/mTOR signaling pathway could be inhibited by these two compounds. An autophagy inhibitor, 3-methyladenine, could partially reverse cell viability and conversely change the ratio of LC3II/LC3I and the protein expression of Bcl-2 and Kim-1. Thus this study helped to understand that 23B and 24A induced autophagy resulted in apoptosis and nephrotoxicity through inhibiting PI3K/Akt/mTOR signaling pathway, facilitating further studies for nephrotoxicity induced by these two compounds and could be beneficial for safe use of Rhizoma alismatis in clinic.

Activity of andrographolide against dengue virus

Dengue is the most prevalent arthropod-transmitted viral illness of humans, with an estimated 100 million symptomatic infections occurring each year and more than 2.5 billion people living at risk of infection. There are no approved antiviral agents against dengue virus, and there is only limited introduction of a dengue vaccine in some countries. Andrographolide is derived from Andrographis paniculata, a medicinal plant traditionally used to treat a number of conditions including infections. The antiviral activity of andrographolide against dengue virus (DENV) serotype 2 was evaluated in two cell lines (HepG2 and HeLa) while the activity against DENV 4 was evaluated in one cell line (HepG2). Results showed that andrographolide had significant anti-DENV activity in both cell lines, reducing both the levels of cellular infection and virus output, with 50% effective concentrations (EC₅₀) for DENV 2 of 21.304 μM and 22.739 μM for HepG2 and HeLa respectively. Time of addition studies showed that the activity of andrographolide was confined to a post-infection stage. These results suggest that andrographolide has the potential for further development as an anti-viral agent for dengue virus infection.

Andrographolide-induced apoptosis in human renal tubular epithelial cells: Roles of endoplasmic reticulum stress and inflammatory response

Andrographolide sodium bisulfate as a kind of soluble derivative of andrographolide (AD), is obviously known to be nephrotoxicity, but AD has not been reported clearly. Our study aimed to investigate the induction of apoptosis in human renal tubular epithelial (HK-2) cells by AD and its possible mechanism. Our results demonstrated that AD (0-250μmol/L) inhibited Hk-2 cells proliferation in a dose- and time-dependent manner and induced apoptosis, accompanied by decreased of superoxide dismutase (SOD) activity and increased of malondialdehvde (MDA) content. Simultaneously, AD regulated the expression of endoplasmic reticulum (ER) molecular chaperone glucose-regulated protein 78 (GRP78/Bip) protein, elevated the expressions of C/EBP homologous protein (CHOP) and Caspase-4, indicating activation of ER stress signaling, and induced the alterative expression of kidney injury molecule-1 (KIM-1), tumor necrosis factor-α (TNF-α) and Interleukin-6 (IL-6) proteins. It provided evidence that ER stress and inflammation would be significant mechanisms responsible for AD-induced apoptosis in addition to oxidative stress.

Activity of andrographolide against chikungunya virus infection

Chikungunya virus (CHIKV) is a re-emerging mosquito-borne alphavirus that has recently engendered large epidemics around the world. There is no specific antiviral for treatment of patients infected with CHIKV, and development of compounds with significant anti-CHIKV activity that can be further developed to a practical therapy is urgently required. Andrographolide is derived from Andrographis paniculata, a herb traditionally used to treat a number of conditions including infections. This study sought to determine the potential of andrographolide as an inhibitor of CHIKV infection. Andrographolide showed good inhibition of CHIKV infection and reduced virus production by approximately 3log₁₀ with a 50% effective concentration (EC₅₀) of 77 μM without cytotoxicity. Time-of-addition and RNA transfection studies showed that andrographolide affected CHIKV replication and the activity of andrographolide was shown to be cell type independent. This study suggests that andrographolide has the potential to be developed further as an anti-CHIKV therapeutic agent.

Proteomic identification of mitochondrial targets involved in andrographolide sodium bisulfite-induced nephrotoxicity in a rat model

Our previous works have indicated that the mitochondrion is the primary target of nephrotoxicity induced by andrographolide sodium bisulfate (ASB), but the mechanisms of ASB-induced nephrotoxicity have remained largely unknown. In this study, proteomic analysis was used to explore the changes in the renal mitochondrial proteome in SD rats after treatment with ASB. SD rats were intraperitoneally administered with ASB (100, 600mg/kg/d) for 7 days. Renal impairment was evaluated by pathological observation. Two-dimensional gel electrophoresis (2-DE), as well as matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS), was applied for the identification of mitochondrial protein and was validated by Western blotting. Protein-protein interactions were analyzed using a Web-based bioinformatics tool (STRING, version 9.1). Rat kidneys exhibited histopathological changes after treatment with ASB, and 13 proteins were significantly changed, including ES1 protein homolog, heat shock cognate 71kDa protein, peroxiredoxin-1 (Prdx1), cytochrome C oxidase subunit 5B (COX5B), prohibitin (PHB), threonine-tRNA ligase, pyruvate dehydrogenase E1 component subunit beta (PDH-β), voltage-dependent anion-selective channel protein 2 (VDAC2), voltage-dependent anion-selective channel protein 1 (VDAC1), adenylate kinase 2 (KAD2) and others. These data demonstrated that the expression levels of several proteins significantly changed in the mitochondria, and these proteins could be candidate biomarkers for ASB-induced nephrotoxicity.

Metabolic changes in the urine of andrographolide sodium bisulfite-treated rats

In recent years, andrographolide sodium bisulfite (ASB) has been reported to cause acute renal failure frequently in clinical practice. We hypothesized that changes in metabolic profile could have occurred after administration of ASB. To investigate the metabolic changes caused by ASB-induced nephrotoxicity, metabonomics method was utilized to depict the urine metabolic characteristics and find the specific urine biomarkers associated with ASB-induced nephrotoxicity. Sprague-Dawley rats were randomly assigned into three experimental groups. They received a single daily injection of vehicle (0.9% sodium chloride solution) or ASB at a dose of 100 or 600 mg kg−1 day−1 for 7 days. Twelve-hour urine was collected after the last administration. The routine urinalysis was measured by a urine automatic analyzer while urinary metabolites were evaluated using gas chromatography/mass spectrometry. The acquired data were processed by multivariate principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and orthogonal PLS-DA. After 7-day administration of ASB, the positive urine samples in protein, occult blood, and ketones were increased, presenting dose dependence. The PCA and PLS-DA models were capable of distinguishing the difference between ASB-treated group and control. Biomarkers such as 1,5-anhydroglucitol, d-erythro-sphingosine, and 2-ketoadipate were identified as the most influential factors in ASB-induced nephrotoxicity.

The NADPH oxidase inhibitor DPI can abolish hypoxia-induced apoptosis of human kidney proximal tubular epithelial cells through Bcl2 up-regulation via ERK activation without ROS reduction

AIMS

Ischemia/reperfusion injury (IRI), resulting from hypoxic damage within a graft, is the leading cause of cell death and graft rejection. In this study, we investigated whether a HIF-1α inhibitor or various antioxidants were able to prevent ischemic injury in a cellular model in which experimental hypoxia was induced using CoCl2.

MAIN METHODS

The ischemic injury induced in HK-2 cells by CoCl2 was validated by increased reactive oxygen species (ROS) production, reduced cell viability, and increased apoptosis at different times and doses. The preventative effects of various anti-oxidants on ischemic injury were evaluated using ROS levels, cell viability, and apoptosis. The MAPK phosphorylation status and Bcl2/Bax expression levels were evaluated after treatment with various antioxidants.

KEY FINDINGS

The increase in ROS induced by hypoxia was significantly inhibited by NAC and CAPE, but not by any other treatment. The reduction in cell viability induced by CoCl2 was significantly inhibited by NAC and DPI, but not by any other treatment. The apoptosis induced by CoCl2 was also significantly inhibited by NAC and DPI, but not by any other treatment. Moreover, NAC and DPI prevented CoCl2-induced apoptosis in HK-2 cells in a dose- and time-dependent manner. Treatment of CoCl2 and HK-2 cells treated with DPI, but not NAC, significantly induced ERK activation and Bcl2 expression. NAC and DPI treatment prevented the apoptosis of cells cultured under hypoxic conditions.

SIGNIFICANCE

Our results suggest that DPI should be investigated further as a novel protective agent that prevents kidney ischemia.

Autophagy in ethanol-exposed liver disease

Ethanol metabolism in hepatocytes causes the generation of reactive oxygen species, endoplasmic reticulum stress and alterations in mitochondrial energy and REDOX metabolism. In ethanol-exposed liver disease, autophagy not only acts as a cleanser to remove damaged organelles and cytosolic components, but also selectively clears specific targets such as lipid droplets and damaged mitochondria. Moreover, ethanol appears to play a role in protecting hepatocytes from apoptosis at certain concentrations. This article describes the evidence, function and potential mechanism of autophagy in ethanol-exposed liver disease and the controversy surrounding the effects of ethanol on autophagy.