Paeoniflorin targets apoptosis and ameliorates fibrosis in murine schistosomiasis mansoni : A novel insight

Research progress in the treatment of schistosomiasis with traditional Chinese medicine

ETHNOPHARMACOLOGICAL RELEVANCE

Schistosomiasis, caused by infection with organisms of the Schistoma genus, is a parasitic and infectious disease that poses a significant risk to human health. Schistosomiasis has been a widespread issue in China for at least 2000 years. Traditional Chinese medicine (TCM) has a rich history of treating this disease, and the significant theoretical and practical knowledge attained therein may be useful in modern practice.

AIM OF THE STUDY

To comprehensively review TCM for the treatment of schistosomiasis, summarize the molecular basis, mechanism of action, active ingredients and formulas of TCM, and clarify the value of TCM for expanding drug options for the clinical treatment of schistosomiasis.

MATERIALS AND METHODS

In PubMed, Web of Science, ScienceDirect, Google Scholar and CNKI databases, "Schistosomiasis", "Schistosoma mansoni", "Schistosoma japonicum", "Liver fibrosis" and "Granuloma" were used as the key words. Information related to in vivo animal studies and clinical studies of TCM for the treatment of schistosomiasis in the past 25 years was retrieved, and the inclusion criteria focused on medicinal plants that had a history of use in China.

RESULTS

In this study, we collected and organized a large amount of literature on the treatment of schistosomiasis by TCM. TCM exerts therapeutic effects through antischistosomal and immunomodulatory effects, suppresses HSC activation and proliferation, reduces ECM deposition, and inhibits oxidative stress and other activities. The treatment of schistosomiasis by TCM has a unique advantage, especially for the treatment of schistosomal liver fibrosis, and the treatment of schistosomiasis with TCM in combination with praziquantel is superior to monotherapy.

CONCLUSION

Schistosomiasis remains a global public health problem, and TCM has made significant progress in the prevention and treatment of schistosomiasis and is a potential source of drugs for the treatment of schistosomiasis. However, research on drug screening and the mechanism of action of TCM for the treatment of schistosomiasis is lacking, and further studies and research are needed.

Therapeutic Potential of Natural Products in the Treatment of Schistosomiasis

It is estimated that 250 million people worldwide are affected by schistosomiasis. Disease transmission is related to the poor sanitation and hygiene habits that affect residents of impoverished regions in tropical and subtropical countries. The main species responsible for causing disease in humans are Schistosoma Mansoni, S. japonicum, and S. haematobium, each with different geographic distributions. Praziquantel is the drug predominantly used to treat this disease, which offers low effectiveness against immature and juvenile parasite forms. In addition, reports of drug resistance prompt the development of novel therapeutic approaches. Natural products represent an important source of new compounds, especially those obtained from plant sources. This review compiles data from several in vitro and in vivo studies evaluating various compounds and essential oils derived from plants with cercaricidal and molluscicidal activities against both juvenile and adult forms of the parasite. Finally, this review provides an important discussion on recent advances in molecular and computational tools deemed fundamental for more rapid and effective screening of new compounds, allowing for the optimization of time and resources.

Paeoniflorin attenuates DHEA-induced polycystic ovary syndrome via inactivation of TGF-β1/Smads signaling pathway in vivo

Polycystic ovarian syndrome (PCOS) is one of the most common reproductive endocrine disorders which are involved in complicated and unknown pathogenic mechanisms. Paeoniflorin (PAE) plays a significant anti-fibrotic role according to previous studies. The aim of the present study was to investigate the effect of PAE on ovarian fibrosis and its underlying mechanism in PCOS development. An animal model of PCOS was established by subcutaneous injection of 60mg/kg/d dehydroepiandrosterone (DHEA) for 35 consecutive days. Rats in PAE-L, PAE-M and PAE-H groups were administrated by gavage with PAE (20, 40, 80 mg/kg/d) for 4 weeks. Our results indicated that DHEA-induced PCOS rats showed similar phenotypes with PCOS patients. PAE could significantly block the DHEA-induced decline of ovary weight and organ coefficient, shorten the prolonged diestrus period, and regulate the irregular estrous cycle of PCOS rats. Moreover, PAE regulated reproductive hormone levels and improved ovarian fibrosis induced by DHEA. PAE treatment could also reduce the expression levels of TGF-β1 and Smad3, and increase the expression levels of Smad7 and MMP2. In conclusion, PAE significantly attenuated the ovarian fibrosis in PCOS, which could be mediated by TGF-β1/Smads signaling pathway. Herein, PAE can be used for the treatment of ovarian fibrosis in PCOS progression.

A comprehensive review of natural products to fight liver fibrosis: Alkaloids, terpenoids, glycosides, coumarins and other compounds

The discovery of drugs to treat liver fibrosis has long been a challenge over the past decades due to its complicated pathogenesis. As a primary approach for drug development, natural products account for 30% of clinical drugs used for disease treatment. Therefore, natural products are increasingly important for their medicinal value in liver fibrosis therapy. In this part of the review, special focus is placed on the effect and mechanism of natural compounds, including alkaloids, terpenoids, glycosides, coumarins and others. A total of 36 kinds of natural compounds demonstrate significant antifibrotic effects in various liver fibrosis models in vivo and in hepatic stellate cells (HSCs) in vitro. Revealing the mechanism will provide further basis for clinical conversion, as well as accelerate drug discovery. The mechanism was further summarized with the finding of network regulation by several natural products, such as oxymatrine, paeoniflorin, ginsenoside Rg1 and taurine. Moreover, there are still improvements needed in investigating clinical efficacy, determining mechanisms, and combining applications, as well as semisynthesis and modification. Therefore, natural products area promising resource for agents that protect against liver fibrosis.

Total glucosides of paeony: A review of its phytochemistry, role in autoimmune diseases, and mechanisms of action

ETHNOPHARMACOLOGICAL RELEVANCE

Paeoniae Radix Alba (PRA, called baishao in China), the root of Paeonia lactiflora Pall., has shown a rich medicinal value for more than 2000 years. PRA is used in local medicine and traditional medicine for autoimmune diseases associated with inflammation. At present, total glucosides of paeony (TGP), the main active ingredient of PRA, has been developed into a preparation for the treatment of autoimmune diseases, as TGP exhibits the effect of regulating immunity, anti-inflammatory, and analgesic effects.

AIM OF THE REVIEW

TGP was developed and applied to inflammation-related autoimmune diseases in modern clinical practice. Based on its application in traditional prescriptions, this article reviews PRA's botany and phytochemistry (including its extraction process and quality control), and discusses the clinical application and pharmacological research of TGP as an anti-inflammatory drug from the perspective of ethnopharmacology. Additionally, we review modern pharmacological and molecular-target research on TGP and discuss the mechanisms of TGP in treating autoimmune diseases. Through a systematic literature review, we also highlight the clinical efficacy of TGP in the treatment of immune diseases, and provide a reference for the continued scientific development and quality control of TGP so that its wider application and clinical value can be fully realized.

MATERIALS AND METHODS

Literature search was conducted through the Web of Science, Baidu Scholar, ScienceDirect, PubMed, CNKI, and WanFang DATA using the keywords "Total glucosides of paeony", "Paeonia lactiflora Pall. ", "Paeonia veitchii Lynch", "Paeoniae Radix Alba or white peony", "Paeoniae Radix Rubra or red peony", "Paeoniflorin", "Albiflorin", "Autoimmune diseases", and their combinations. In addition, information was collected from relevant textbooks, reviews, and documents.

RESULTS

Approximately 15 compounds have been identified in TGP, of which paeoniflorin and albiflorin are the most common constituents. In recent years, studies have found that TGP and its main chemical components are effective in the treatment of autoimmune diseases, such as rheumatoid arthritis, psoriasis, oral lichen planus, and Sjogren's syndrome. TGP has a variety of pharmacological effects related to PRA traditional effects, including anti-organ-damage, anti-inflammatory, analgesic, antioxidant, cardiovascular, and nervous-system protection. Previously published reports on TGP treatment of autoimmune diseases have shown that TGP regulates intracellular pathways, such as the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), mitogen-activated protein kinase (MAPK), and phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathways. However, there is no standardized preparation method for TGP, and there is insufficient quality control of formulations. Many related pharmacological studies have not tested TGP components, and the validity of such pharmacological results requires further verification.

CONCLUSIONS

Modern pharmacological research on TGP is based on the traditional usage of PRA, and its folk medicinal value in the treatment of autoimmune diseases has now been verified. In particular, TGP has been developed into a formulation used clinically for the treatment of autoimmune diseases. The combination of TGP capsules and chemicals to treat autoimmune diseases has the effect of increasing efficacy and reducing toxicity. Based on further research on its preparation, quality control, and mechanisms of action, TGP is expected to eventually play a greater role in the treatment of autoimmune diseases.

Investigating the antifibrotic effect of the antiparasitic drug Praziquantel in in vitro and in vivo preclinical models

Tissue fibrosis underlies the majority of human mortality to date with close to half of all reported deaths having a fibrotic etiology. The progression of fibrosis is very complex and reputed irreversible once established. Although some preventive options are being reported, therapeutic options are still scarce and in very high demand, given the rise of diseases linked to fibroproliferative disorders. Our work explored four platforms, complementarily, in order to screen preventive and therapeutic potentials of the antiparasitic drug Praziquantel as a possible antifibrotic. We applied the mouse CCl₄-driven liver fibrosis model, the mouse chronic schistosomiasis liver fibrosis model, as well as novel 2D and 3D human cell-based co-culture of human hepatocytes, KCs (Kupffer cells), LECs (Liver Endothelial Cells), HSCs (Hepatic Stellate Cells) and/or myofibroblasts to mimic in vivo fibrotic responses and dynamics. Praziquantel showed some effect on fibrosis marker when preventively administered before severe establishment of fibrosis. However, it failed to potently reverse already established fibrosis. Together, we provided a novel sophisticated multi-assay screening platform to test preventive and therapeutic antifibrotic candidates. We further demonstrated a direct preventive potential of Praziquantel against the onset of fibrosis and the confirmation of its lack of therapeutic potential in reversing already established fibrosis.

Paeoniflorin, a Natural Product With Multiple Targets in Liver Diseases-A Mini Review

Paeoniflorin is derived from Paeonia suffruticosa Andr., Paeonia lactiflora Pall., or Paeonia veitchii Lynch and has been used in traditional medical applications for more than 2,000 years. Paeoniflorin is a monoterpenoid glycoside with various effects on liver diseases. Recent studies have revealed that paeoniflorin demonstrates a wide range of activities, including hepatic protection, cholestasis alleviation, liver fibrosis attenuation, nonalcoholic fatty liver disease prevention, and hepatocellular carcinoma inhibition involved in multiple pathways. Moreover, anti-inflammation, antioxidation, and immune regulation with the regulation of TLR4-NF-κB, ROCK/NF-κB, HO-1, mitochondria-dependent as well as HMGB1‐TLR4 signaling pathways are correlated with hepatic protection in liver injury and nonalcoholic fatty liver disease. Antioxidative mechanisms, anti-inflammation, and hepatic transporter regulation involved in NOX4, PI3K/Akt/Nrf2, NF‐κB, NTCP, BSEP, as well as MRP2 signals are mainly relevant to the anticholestatic effect of paeoniflorin. The inhibition of hepatic stellate cell activation and alleviation of extracellular matrix deposition via vast signals such as mTOR/HIF-1α, TGF-β1/Smads, and JAK2/STAT6 are primarily involved in the antifibrotic effect of paeoniflorin. The regulation of macrophages also contributes to the alleviation effect on liver fibrosis. In addition, the reduction of invasion, metastasis, and adhesion and the induction of apoptosis-related targets, including Bax, Bcl-2, and caspase-3, are related to its effect on hepatocellular carcinoma. The literature indicates that paeoniflorin might have potent efficacy in complex liver diseases and demonstrates the profound medicinal value of paeoniflorin.

A review for the anti-inflammatory effects of paeoniflorin in inflammatory disorders

Inflammatory disorders result from abnormal immune response and their incidence has increased recently. Thus, there is an urgent need to discover new treatments for inflammatory disorders. In recent years, the natural products contained in Chinese herbs have attracted much attention worldwide owing to their anti-inflammatory effects. Paeoniflorin (PF) is a bioactive compound purified from the Chinese herb Paeonia lactiflora and reports have recently emerged suggesting the great potential of P. lactiflora as an agent to counter inflammatory disorders. The anti-inflammatory effects of PF have been revealed by in vitro studies and in vivo animal experiments of different inflammatory disorders, including rheumatoid arthritis, inflammatory bowel disease, psoriasis, and asthma. This review systematically describes the recent progress of studies on the mechanism of PF and its therapeutic potential in inflammatory disorders.

NF-κB signaling and crosstalk during carcinogenesis

Transcription factors (TFs) are proteins that control the transcription of genetic information from DNA to mRNA by binding to specific DNA sequences either on their own or with other proteins as a complex. TFs thus support or suppress the recruitment of the corresponding RNA polymerase. In general, TFs are classified by structure or function. The TF, Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), is expressed in all cell types and tissues. NF-κB signaling and crosstalk are involved in several steps of carcinogenesis including in sequences involving pathogenic stimulus, chronic inflammation, fibrosis, establishment of its remodeling to the precancerous niche (PCN) and transition of a normal cell to a cancer cell. Triggered by various inflammatory cytokines, NF-κB is activated along with other TFs with subsequent stimulation of cell proliferation and inhibition of apoptosis. The involvement of NF-κB in carcinogenesis provides an opportunity to develop anti-NF-κB therapies. The complexity of these interactions requires that we elucidate those aspects of NF-κB interactions that play a role in carcinogenesis, the sequence of events leading to cancer.

Paeoniflorin in experimental BALB/c mansoniasis: A novel anti-angiogenic therapy

Chronic hepatic schistosomiasis causes portal hypertension, fibrosis and lethal hepatosplenic complications. Previous studies focused mainly on schistosomicidal drugs and neglected the therapeutic approaches against the vascular complications after portal hypertension. Investigating a novel anti-angiogenic therapy is an urgent. The current study is to evaluate the performance of Paeoniflorin (PAE) as an anti-angiogenic therapy, being a powerful anti-fibrotic, compared to artemether (ART) and praziqantel (PZQ) in schistosomiasis mansoni BALB/c mice. Thirty two laboratory bred male BALB/c Swiss albino mice. The mice were classified into four groups (8 mice each), control infected (CI), PZQ (300 mg/kg/12 h), ART (0.1 ml/mg/d) and PAE (50 mg/kg/d) treated groups for one month. All mice groups were sacrificed 15 weeks post infection for assessment of the drugs' efficacy by parasitological, histopathological and immunohistochemical studies. Our results in PAE group showed marked reduction in the mean egg count/gram stool, worm burden, egg count/gram liver tissue, granuloma diameter and pro-angiogenic factors as vascular endothelial growth factor (VEGF), Proliferating cell nuclear antigen (PCNA), alpha-smooth muscle actin (α-SMA) and CD34; conversely, there was an augmentation of the tissue inhibitor metalloproteinases-2 (TIMP-2) as an anti-angiogenic expression that was exceeded ART and PZQ treated groups compared to CI group (p˂0.001). Conclusively, PAE has an anti-angiogenic impact with no vascular proliferative activity or recanalization, no micro-vessel density (MVD) changes, granuloma resolution and fibrosis regression. PAE is predicted to be a potential therapy for chronic hepatic diseases associated with fibrosis and angiogenesis, hopeful in protecting from advanced serious complications; cancer and metastasis.

Chronic schistosomiasis suppresses HIV-specific responses to DNA-MVA and MVA-gp140 Env vaccine regimens despite antihelminthic treatment and increases helminth-associated pathology in a mouse model

Future HIV vaccines are expected to induce effective Th1 cell-mediated and Env-specific antibody responses that are necessary to offer protective immunity to HIV infection. However, HIV infections are highly prevalent in helminth endemic areas. Helminth infections induce polarised Th2 responses that may impair HIV vaccine-generated Th1 responses. In this study, we tested if Schistosoma mansoni (Sm) infection altered immune responses to SAAVI candidate HIV vaccines (DNA and MVA) and an HIV-1 gp140 Env protein vaccine (gp140) and whether parasite elimination by chemotherapy or the presence of Sm eggs (SmE) in the absence of active infection influenced the immunogenicity of these vaccines. In addition, we evaluated helminth-associated pathology in DNA and MVA vaccination groups. Mice were chronically infected with Sm and vaccinated with DNA+MVA in a prime+boost combination or MVA+gp140 in concurrent combination regimens. Some Sm-infected mice were treated with praziquantel (PZQ) prior to vaccinations. Other mice were inoculated with SmE before receiving vaccinations. Unvaccinated mice without Sm infection or SmE inoculation served as controls. HIV responses were evaluated in the blood and spleen while Sm-associated pathology was evaluated in the livers. Sm-infected mice had significantly lower magnitudes of HIV-specific cellular responses after vaccination with DNA+MVA or MVA+gp140 compared to uninfected control mice. Similarly, gp140 Env-specific antibody responses were significantly lower in vaccinated Sm-infected mice compared to controls. Treatment with PZQ partially restored cellular but not humoral immune responses in vaccinated Sm-infected mice. Gp140 Env-specific antibody responses were attenuated in mice that were inoculated with SmE compared to controls. Lastly, Sm-infected mice that were vaccinated with DNA+MVA displayed exacerbated liver pathology as indicated by larger granulomas and increased hepatosplenomegaly when compared with unvaccinated Sm-infected mice. This study shows that chronic schistosomiasis attenuates both HIV-specific T-cell and antibody responses and parasite elimination by chemotherapy may partially restore cellular but not antibody immunity, with additional data suggesting that the presence of SmE retained in the tissues after antihelminthic therapy contributes to lack of full immune restoration. Our data further suggest that helminthiasis may compromise HIV vaccine safety. Overall, these findings suggested a potential negative impact on future HIV vaccinations by helminthiasis in endemic areas.

Chronic parasitic worm infections are thought to reduce the efficacy of vaccines. Given that HIV and worm infections are common in sub-Saharan Africa (SSA) and their geographical distribution vastly overlaps, it is likely that future HIV vaccines in SSA will be administered to a large proportion of people with chronic worm infections. This study examined the impact of S. mansoni worm infections on the immunogenicity of candidate HIV vaccines in a mouse model. S. mansoni worm-infected animals had lower magnitudes of HIV vaccine responses compared with uninfected animals and elimination of worms by praziquantel treatment prior to vaccination conferred only partial restoration of normal immune responses to vaccination. The presence of S. mansoni eggs trapped in the tissues in the absence of live infection was associated with poor vaccine responses. In addition, this study found that effective immunization with some HIV vaccine regimens could potentially worsen worm-associated pathology when given to infected individuals. These novel findings suggest further research in HIV vaccines and future vaccination policies regarding the current clinical vaccines and future HIV vaccination with respect to parasitic worm infections especially in SSA.