α-Lipoic Acid Vaginal Administration Contrasts Inflammation and Preterm Delivery in Rats

Protective effect of alpha‑lipoic acid against in utero cytarabine exposure-induced hepatotoxicity in rat female neonates

Cytarabine, an anti-metabolite drug, remains the mainstay of treatment for hematological malignancies. It causes various toxic effects including teratogenicity. Alpha lipoic acid (ALA) is a natural antioxidant reported to offer protection against hepatotoxicity induced by various pathological conditions, drugs, or chemicals. We investigated the protective effect of ALA against prenatal cytarabine exposure-induced hepatotoxicity in rat female neonates. A total of 30 dams were randomly assigned to five groups and received normal saline, ALA 200 mg/kg, cytarabine 12.5 mg/kg, cytarabine 25 mg/kg, and cytarabine 25 mg/kg + ALA 200 mg/kg, respectively, from gestational day (GD)8 to GD21. Cytarabine and ALA were administered via intraperitoneal and oral (gavage) routes, respectively. On postnatal day (PND)1, all the live female neonates (pups) were collected and weighed. The blood and liver from pups were carefully collected and used for histopathological, and biochemical evaluations. A significant and dose-dependent decrease in maternal food intake and weight gain was observed in the pregnant rats (dams) of the cytarabine groups as compared to the dams of the control group. The pups exposed to cytarabine showed a significant and dose-dependent (a) decrease in body weight, liver weight, hepatosomatic index, catalase, superoxide dismutase, glutathione, glutathione peroxidase, serum albumin levels and (b) increase in malondialdehyde, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase, AST/ALT ratio, and histopathological anomalies. Maternal co-administration of ALA ameliorated these biochemical changes and histopathological abnormalities by combating oxidative stress. Future studies are warranted to explore the molecular mechanisms involved in the ALA's protective effects against prenatal cytarabine-induced hepatotoxicity.

Bioinformatics and integrated pharmacology network to identify the therapeutic targets and potential molecular mechanism of alpha-lipoic acid on primary ovarian insufficiency

Women experiencing primary ovarian insufficiency (POI) are more likely to experience infertility, and its incidence is increasing worldwide annually. Recently, the role of alpha-lipoic acid (ALA) in the treatment of POI has been reported. However, details of the potential pharmacological targets and related molecular pathways of ALA remain unclear and need to be elucidated. Thus, this study aims to elucidate the potential therapeutic target and related molecular mechanism of ALA on POI. First, the potential targets of POI and ALA-related targets were downloaded from online public databases. Subsequently, the overlapped target genes between POI and ALA were acquired, and gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG) analysis, protein-protein interaction (PPI) networks were performed and constructed. Finally, molecular docking was performed to verify protein-to-protein effect. A total of 152 potential therapeutic targets were identified. The biological processes of the intersecting targets were mainly involved in the cellular response to peptides, response to xenobiotic stimuli, and response to peptide hormones. The highly enriched pathways were the cAMP, PI3K/AKT, estrogen, progesterone mediated oocyte maturation, and apoptosis signaling pathways. The top 10 hub targets for ALA in the treatment of POI were STAT3, STAT1, CASP3, MTOR, PTGS2, CASP8, HSP90AA1, PIK3CA, MAPK1, and ESR1. The binding between ALA and all top hub targets were verified using the molecular docking analysis. In summary, using the systematic integrated pharmacology network and bioinformatics analysis, this study illustrated that ALA participates in the treatment of POI via multiple targets and multiple pathways mechanisms.

Bilirubin induces microglial NLRP3 inflammasome activation in vitro and in vivo

Despite current advancements in neonatal care, hyperbilirubinemia resulting in bilirubin-induced neurological dysfunction (BIND) continues to be one of the major reasons of mortality or lifelong disability. Although the exact mechanisms underlying brain injury upon bilirubin exposure remains unelucidated, inflammation is considered to be one of the major contributors to BIND. This study investigates the role of the NLRP3 inflammasome in bilirubin-induced injury using in vitro and in vivo models. We successfully demonstrated that the upregulation of NLRP3 expression is significantly associated with the release of active caspase-1 and IL-1β in N9 microglial cells exposed to bilirubin. Functional in vitro experiments with NLRP3 siRNA confirms that bilirubin-induced inflammasome activation and cell death are mediated by the NLRP3 inflammasome. Following injection of bilirubin into the cisterna magna of a neonatal mouse, activation of the NLRP3 inflammasome and microglia were determined by double staining with Iba1-NLRP3 and Iba1-Caspase-1. Upon injection of bilirubin into the cisterna magna, neuronal loss was significantly higher in the wild-type mouse compared to Nlrp3^-/- and Caspase-1^-/- strains. Collectively, these data indicate that NLRP3 inflammasome has a crucial role in microglial activation and bilirubin-induced neuronal damage.

Maternal supplementation of α-lipoic acid attenuates prenatal cytarabine exposure-induced oxidative stress, steroidogenesis suppression and testicular damage in F1 male rat fetus

Background

Cytarabine (Ara-C) is an anticancer drug, which is considered as the mainstay in the treatment of hematological malignancies, known to cause various teratogenic effects. Alpha-lipoic acid (ALA) is a natural antioxidant and its supplementation proved to improve pregnancy outcomes in several pathological conditions. We aimed at exploring the benefits of maternal supplementation of ALA against in-utero Ara-C exposure-induced testicular toxicity in rat fetuses.

Methods

Pregnant rats (dams) received normal saline (control group), ALA 200 mg/kg (ALA group), Ara-C 12.5 mg/kg (Ara-C 12.5 group), Ara-C 25 mg/kg (Ara-C 25 group), and Ara-C 25 mg/kg + ALA 200 mg/kg (protection group) from gestational day (GD)8 to GD21. Ara-C and ALA were administered via the intraperitoneal and oral routes, respectively. The day of parturition was considered as postnatal day (PND)1. On PND1, all the live male pups were collected. The maternal parameters evaluated include (a) food intake, (b) bodyweight, and (c) oxidative stress (OS) markers. The fetal parameters evaluated include (a) bodyweight, (b) anogenital distances (AGD), (c) testicular weight (d) testicular testosterone levels (e) testicular histopathology, and (f) morphometrical parameters.

Results

A significant and dose-dependent decrease in maternal food intake, weight gain, and an increase in oxidative stress (OS) were observed in the pregnant rats of the Ara-C groups as compared to pregnant rats of the control group. Further, a significant and dose-dependent (a) reduction in bodyweight, AGD, testicular weight, and testosterone levels, (b) increase in OS, and (c) structural and morphometrical anomalies in fetal testes were observed in fetuses of Ara-C groups as compared to fetuses of the control rats. These deleterious effects observed in the Ara-C groups were found to be diminished in the pregnant rats and fetuses of the Protection group as compared to the pregnant rats and fetuses of the Ara-C 25 group.

Conclusions

From the results of this study, we conclude that the maternal supplementation of ALA may ameliorate the Ara-C exposure-induced impairment in prenatal development and function of the testes in the rat fetuses. However, future experimental and clinical studies are warranted to explore the possible mechanisms involved in the protection offered by maternal supplementation of ALA against Ara-C induced testicular toxicity.

Graphical Abstract

Human Chorionic Gonadotropin Modulates the Transcriptome of the Myometrium and Cervix in Late Gestation

Human chorionic gonadotropin (hCG) is a critical hormone for the establishment and maintenance of pregnancy. hCG administration prevents the onset of preterm labor in mice; yet, the transcriptomic changes associated with this tocolytic effect that take place in the myometrium and cervix have not been elucidated. Herein, we implemented both discovery and targeted approaches to investigate the transcriptome of the myometrium and cervix after hCG administration. Pregnant mice were intraperitoneally injected with 10 IU of hCG on 13.0, 15.0, and 17.0 days post coitum, and the myometrium and cervix were collected. RNA sequencing was performed to determine differentially expressed genes, enriched biological processes, and impacted KEGG pathways. Multiplex qRT-PCR was performed to investigate the expression of targeted contractility- and inflammation-associated transcripts. hCG administration caused the differential expression of 720 genes in the myometrium. Among the downregulated genes, enriched biological processes were primarily associated with regulation of transcription. hCG administration downregulated key contractility genes, Gja1 and Oxtr, but upregulated the prostaglandin-related genes Ptgfr and Ptgs2 and altered the expression of inflammation-related genes in the myometrium. In the cervix, hCG administration caused differential expression of 3348 genes that were related to inflammation and host defense, among others. The downregulation of key contractility genes and upregulation of prostaglandin-related genes were also observed in the cervix. Thus, hCG exerts tocolytic and immunomodulatory effects in late gestation by altering biological processes in the myometrium and cervix, which should be taken into account when considering hCG as a potential treatment to prevent the premature onset of labor.

Alpha-lipoic acid ameliorates cytarabine-induced developmental anomalies in rat fetus

Cytarabine (Ara-C) is a nucleoside analogue used in the treatment of cancers and viral infections. It has teratogenic potential and causes a variety of birth defects in fetuses. Alpha-lipoic acid (ALA) is a natural antioxidant offers protection against the developmental toxicity induced by drug- or toxicant-exposure or pathological conditions. This study was aimed at evaluating the protective effect of ALA against Ara-C induced developmental toxicity in rat fetus. Pregnant rats divided into five groups and received normal saline, ALA200 mg/kg, Ara-C12.5 mg/kg, Ara-C25 mg/kg and, Ara-C25 mg/kg plus ALA200 mg/kg respectively from gestational day (GD) 8 to GD14 and sacrificed on GD21. Ara-C treatment led to a significant and dose-dependent decrease in food intake, weight gain, placental weight, and an increase in oxidative stress in pregnant rats. Further, the in-utero exposure to Ara-C led to an increase in fetal mortality, resorptions, oxidative stress, external morphological anomalies and limb abnormalities, and impaired ossification. Co-administration of ALA resulted in amelioration of the footprints of Ara-C induced toxicity in pregnant rats as well as the fetus. These findings indicate that the ALA supplementation offers protection against developmental toxicity caused by Ara-C prenatal exposure in rats.

Protective effect of alpha lipoic acid on 4-vinylcyclohexene diepoxide induced primary ovarian failure in female rats

OBJECTIVE

The effects of alpha lipoic acid (ALA) and its possible mechanisms in treating Primary ovarian failure (POF) model was studied with 4 vinylcyclohexene diepoxide (VCD).

MATERIAL AND METHODS

Rats were divided into 4 groups (n = 7) as Control, VCD, VCD + ALA and ALA. POF model was induced by applying VCD intraperitoneally and ALA was administered by oral gavage as 100 mg/day to the VCD + ALA and ALA groups.

RESULTS

At the end of 42 days, ovarian and uterine tissues were received. The number of primordial and primary follicles were increased and corpus luteum and cystic follicles were decreased in ovarian tissues in VCD + ALA group compared to VCD group. Caspase-3 immunoreactivity in follicular cells was decreased in VCD + ALA group compared to VCD group. eNOS immunoreactivity and eNOS levels were decreased in VCD group and increased in VCD + ALA group while iNOS immunoreactivity and iNOS levels were increased in VCD group, decreased in VCD + ALA group in ovary and uterine tissue. Plasma FSH and LH hormone levels were increased in the VCD but decreased in VCD + ALA group. Estradiol level decreased in the VCD group compared to the other groups. The MDA values were significantly increased in the VCD + ALA group compared to VCD group. In addition, the levels of GSH values were decreased in VCD + ALA group compared to VCD group.

CONCLUSION

Alpha lipoic acid treatment of rats with VCD-induced POF had a beneficial effect on reducing ovarian damage by improving histological, immunohistochemical, hormone level and oxidative stress markers. Our results show that ALA is an effective treatment of VCD-induced POF rats.

Insights on the Use of α-Lipoic Acid for Therapeutic Purposes

α-lipoic acid (ALA, thioctic acid) is an organosulfur component produced from plants, animals, and humans. It has various properties, among them great antioxidant potential and is widely used as a racemic drug for diabetic polyneuropathy-associated pain and paresthesia. Naturally, ALA is located in mitochondria, where it is used as a cofactor for pyruvate dehydrogenase (PDH) and α-ketoglutarate dehydrogenase complexes. Despite its various potentials, ALA therapeutic efficacy is relatively low due to its pharmacokinetic profile. Data suggests that ALA has a short half-life and bioavailability (about 30%) triggered by its hepatic degradation, reduced solubility as well as instability in the stomach. However, the use of various innovative formulations has greatly improved ALA bioavailability. The R enantiomer of ALA shows better pharmacokinetic parameters, including increased bioavailability as compared to its S enantiomer. Indeed, the use of amphiphilic matrices has capability to improve ALA bioavailability and intestinal absorption. Also, ALA's liquid formulations are associated with greater plasma concentration and bioavailability as compared to its solidified dosage form. Thus, improved formulations can increase both ALA absorption and bioavailability, leading to a raise in therapeutic efficacy. Interestingly, ALA bioavailability will be dependent on age, while no difference has been found for gender. The present review aims to provide an updated on studies from preclinical to clinical trials assessing ALA's usages in diabetic patients with neuropathy, obesity, central nervous system-related diseases and abnormalities in pregnancy.