Curculigo orchioides protects cisplatin-induced cell damage

Unveiling the Role of Oxidative Stress in Cochlear Hair Cell Death: Prospective Phytochemical Therapeutics against Sensorineural Hearing Loss

Hearing loss represents a multifaceted and pervasive challenge that deeply impacts various aspects of an individual's life, spanning psychological, emotional, social, and economic realms. Understanding the molecular underpinnings that orchestrate hearing loss remains paramount in the quest for effective therapeutic strategies. This review aims to expound upon the physiological, biochemical, and molecular aspects of hearing loss, with a specific focus on its correlation with diabetes. Within this context, phytochemicals have surfaced as prospective contenders in the pursuit of potential adjuvant therapies. These compounds exhibit noteworthy antioxidant and anti-inflammatory properties, which hold the potential to counteract the detrimental effects induced by oxidative stress and inflammation-prominent contributors to hearing impairment. Furthermore, this review offers an up-to-date exploration of the diverse molecular pathways modulated by these compounds. However, the dynamic landscape of their efficacy warrants recognition as an ongoing investigative topic, inherently contingent upon specific experimental models. Ultimately, to ascertain the genuine potential of phytochemicals as agents in hearing loss treatment, a comprehensive grasp of the molecular mechanisms at play, coupled with rigorous clinical investigations, stands as an imperative quest.

Development of Chinese herbal medicine for sensorineural hearing loss

According to the World Health Organization's world report on hearing, nearly 2.5 billion people worldwide will suffer from hearing loss by 2050, which may contribute to a severe impact on individual life quality and national economies. Sensorineural hearing loss (SNHL) occurs commonly as a result of noise exposure, aging, and ototoxic drugs, and is pathologically characterized by the impairment of mechanosensory hair cells of the inner ear, which is mainly triggered by reactive oxygen species accumulation, inflammation, and mitochondrial dysfunction. Though recent advances have been made in understanding the ability of cochlear repair and regeneration, there are still no effective therapeutic drugs for SNHL. Chinese herbal medicine which is widely distributed and easily accessible in China has demonstrated a unique curative effect against SNHL with higher safety and lower cost compared with Western medicine. Herein we present trends in research for Chinese herbal medicine for the treatment of SNHL, and elucidate their molecular mechanisms of action, to pave the way for further research and development of novel effective drugs in this field.

Effects of natural products on cisplatin ototoxicity and chemotherapeutic efficacy

INTRODUCTION

Cisplatin is a very effective chemotherapeutic agent against a variety of solid tumors. Unfortunately, cisplatin causes permanent sensorineural hearing loss in at least two-thirds of patients treated. There are no FDA approved drugs to prevent this serious side effect.

AREAS COVERED

This paper reviews various natural products that ameliorate cisplatin ototoxicity. These compounds are strong antioxidants and anti-inflammatory agents. This review includes mostly preclinical studies but also discusses a few small clinical trials with natural products to minimize hearing loss from cisplatin chemotherapy in patients. The interactions of natural products with cisplatin in tumor-bearing animal models are highlighted. A number of natural products did not interfere with cisplatin anti-tumor efficacy and some agents actually potentiated cisplatin anti-tumor activity.

EXPERT OPINION

There are a number of natural products or their derivatives that show excellent protection against cisplatin ototoxicity in preclinical studies. There is a need to insure uniform standards for purity of drugs derived from natural sources and to ensure adequate pharmacokinetics and safety of these products. Natural products that protect against cisplatin ototoxicity and augment cisplatin's anti-tumor effects in multiple studies of tumor-bearing animals are most promising for advancement to clinical trials. The most promising natural products include honokiol, sulforaphane, and thymoquinone.

Ginsenoside Rc from Panax Ginseng Ameliorates Palmitate-Induced UB/OC-2 Cochlear Cell Injury

By 2050, at least 700 million people will require hearing therapy while 2.5 billion are projected to suffer from hearing loss. Sensorineural hearing loss (SNHL) arises from the inability of the inner ear to convert fluid waves into neural electric signals because of injury to cochlear hair cells that has resulted in their death. In addition, systemic chronic inflammation implicated in other pathologies may exacerbate cell death leading to SNHL. Phytochemicals have emerged as a possible solution because of the growing evidence of their anti-inflammatory, antioxidant, and anti-apoptotic properties. Ginseng and its bioactive molecules, ginsenosides, exhibit effects that suppress pro-inflammatory signaling and protect against apoptosis. In the current study, we investigated the effects of ginsenoside Rc (G-Rc) on UB/OC-2 primary murine sensory hair cell survival in response to palmitate-induced injury. G-Rc promoted UB/OC-2 cell survival and cell cycle progression. Additionally, G-Rc enhanced the differentiation of UB/OC-2 cells into functional sensory hair cells and alleviated palmitate-induced inflammation, endoplasmic reticulum stress, and apoptosis. The current study offers novel insights into the effects of G-Rc as a potential adjuvant for SNHL and warrants further studies elucidating the molecular mechanisms.

5,7-Dihydroxy-4-methylcoumarin modulates the JNK/FoxO1 signaling pathway to attenuate cisplatin-induced ototoxicity by suppressing oxidative stress and apoptosis in vitro

5,7-Dihydroxy-4-methylcoumarin (D4M) is attributed to free radical scavenging effects, with wide application for anti-oxidation. This work aimed to assess D4M's impact on cisplatin-induced ototoxicity. The cell viability was estimated with CCK-8 assay. Apoptosis was detected by the Annexin V-FITC and PI assay. The reactive oxygen species (ROS) level was determined by MitoSOX-Red and CellROX-Green probes. Mitochondrial membrane potential was analyzed with TMRM staining. Immunofluorescence was utilized for hair cells and spiral ganglion neuron detection. Apoptosis-associated proteins were assessed by cleaved caspase-3 and TUNEL staining. These results showed that D4M pretreatment protected hair cells from cisplatin-induced damage, increased cell viability, and decreased apoptosis in House Ear Institute-Organ of Corti1 (HEI-OC1) cells and neonatal mouse cochlear explants. D4M significantly inhibited cisplatin-induced mitochondrial apoptosis and reduced ROS accumulation. In addition, the protective effect of D4M on cisplatin-induced ototoxicity was also confirmed in cochlear hair cells and spiral ganglion neurons in neonatal mice. Mechanistic studies showed that D4M markedly downregulated p-JNK and elevated the expression ratio of p-FoxO1/FoxO1, thereby reducing cisplatin-induced caspase-dependent apoptosis. Meanwhile, D4M-related protection of HEI-OC1 cells was significantly blunted by JNK signaling induction with anisomycin. This study supports the possibility that D4M may be used as a new compound to prevent cisplatin-related hearing loss.

Medical Therapy of Hearing Impairment and Tinnitus with Chinese Medicine: An Overview

The current review gives a comprehensive overview of the recent development in Chinese medicine (CM) for treating several kinds of acquired nerve deafness and tinnitus, as well as links the traditional principle to well-established pharmacological mechanisms for future research. To date, about 24 herbal species and 40 related ingredients used in CM to treat hearing loss and tinnitus are reported for the treatment of endocochlear potential, endolymph growth, lowering toxic and provocative substance aggregation, inhibiting sensory cell death, and retaining sensory transfer. However, there are a few herbal species that can be used for medicinal purposes. Nevertheless, clinical studies have been hampered by a limited population sample, a deficiency of a suitable control research group, or contradictory results. Enhanced cochlear blood flow, antiinflammatory antioxidant, neuroprotective effects, and anti-apoptotic, as well as multi-target approach on different auditory sections of the inner ear, are all possible benefits of CM medications. There are numerous unknown natural products for aural ailment and tinnitus identified in CM that are expected to be examined in the future utilizing various aural ailment models and processes.

Role of Curculigo Orchioides in the Proliferation and Apoptosis of Breast Cancer Michigan Cancer Foundation-7 (MCF-7) Cells Under Network Pharmacology

Based on network pharmacology (NP), the effects of curculigo orchioides (CO) granules alone or CO granules along with tamoxifen on the proliferation and apoptosis (P&A) of human breast cancer (BC) cells were explored. A search database was constructed to obtain the active components (ACs) of CO and related target genes to perform disease mapping, and a BC target map was constructed to perform related pathway enrichment analysis (PEA). The blank control group (CG), estrogen group (EG), and tamoxifen group (TG) were set as controls to observe the effects of CO granules alone and CO granules along with tamoxifen. The PEA showed that the effect of CO on BC may be related to the cooperation of its ACs. The target of action may be related to cell cycle and proliferation, growth factors, metabolic pathways, etc. Different concentrations of CO had different effects, CO granules of various concentrations had no obvious growth-promoting effect (P < 0.05), and so did CO combined with tamoxifen (P > 0.05); high-dose (H-D) CO combined with tamoxifen can induce cell apoptosis (P < 0.05). Through NP, the ACs of CO and related targets of BC were predicted and analyzed. At the same time, it was proved that CO granules are safe in clinical use, and the combined effect of tamoxifen is better in the treatment of estrogen-positive patients, providing reference for the follow-up use of CO in the treatment of BC.

Phytochemistry and Pharmacological Activity of Plants of Genus Curculigo: An Updated Review Since 2013

The genus Curculigo, as a folk herbal medicine, has been used for many years in China, treating impotence, limb limpness, and arthritis of the lumbar and knee joints. The last systematic review of the genus Curculigo was written in 2013, scientifically categorizing the phytochemistry and biological activities. Hitherto, the original compounds and their pharmacological activities were presented as the development of this genus, but there is not an updated review. To conclude the progression of the genus Curculigo, we collected the new literature published from 2013 to 2021 in PubMed, Web of Science, Google Scholar databases, and the Chinese National Knowledge Infrastructure. The novel chlorophenolic glucosides, curculigine, phenolic glycosides, orcinosides and polysaccharides were isolated from Curculigo. The new analyzing methods were established to control the quality of Curculigo as a herbal medicine. In addition, the pharmacological effects of Curculigo focused on anti-diabetes, antibacterial, anti-inflammatory, osteoporosis, antioxidation, etc. The antitumor and neuroprotective activities were newly explored in recent years. The application of herbal medicine was gradually developed in scientific methods. The medicinal value of the genus Curculigo needs to further investigate its pharmacological mechanisms. This new review offers more insights into the exploitation of the pharmacological value of the genus Curculigo.

Stimulated upregulation of HO-1 is associated with inadequate response of gastric and ovarian cancer cell lines to hyperthermia and cisplatin treatment

Heme oxygenase (HO)-1 is a heat shock protein induced by hyperthermia, responsible for cellular resistance to temperature. The aim of this in vitro study was to clarify the response of gastric and ovarian cancer cells to hyperthermic intraperitoneal chemotherapy, following the modulation of HO-1 expression. AGS and OVCAR-3 cells were treated with different temperature regimens, either alone or in combination with an IC₅₀ dose of cisplatin for 1 h. Prior to treatment, HO-1 expression was silenced by short interfering RNA transfection. In OVCAR-3 cells, cisplatin increased HO-1 mRNA expression by 3.73-fold under normothermia and 2.4-fold under hyperthermia; furthermore, these factors similarly increased HO-1 protein expression levels. Exposure to cisplatin under hyperthermia reduced the viability of OVCAR-3 cells by 36% and HO-1-silencing enhanced this effect by 20%. HO-1-silencing under normothermia increased apoptotic rates in cisplatin-treated OVCAR-3 cells by 2.07-fold, and hyperthermia enhanced the effect by 3.09-fold. Semi-quantitative polymerase chain reaction (PCR) cell analysis indicated that exposure to cisplatin decreased the cell index under normothermia, and that hyperthermia boosted this effect in OVCAR-3. In AGS cells, only temperature increased cellular HO-1 levels. Silencing HO-1 in AGS cells at 37°C reduced viability by 16% and increased apoptotic rates 2.63-fold. Hyperthermia did not affect AGS viability; however, apoptosis was increased 6.84-fold. PCR analysis indicated no additional effects of hyperthermia on the AGS cell index. HO-1 is induced in cancer cells by different stressors in a variable manner. In tumors with highly inducible HO-1, prior silencing of this gene could improve the cellular response to hyperthermia and cisplatin.

Traditional oriental medicine for sensorineural hearing loss: Can ethnopharmacology contribute to potential drug discovery?

ETHNOPHARMACOLOGICAL RELEVANCE

In Traditional Oriental Medicine (TOM), the development of hearing pathologies is related to an inadequate nourishment of the ears by the kidney and other organs involved in regulation of bodily fluids and nutrients. Several herbal species have historically been prescribed for promoting the production of bodily fluids or as antiaging agents to treat deficiencies in hearing.

AIM OF REVIEW

The prevalence of hearing loss has been increasing in the last decade and is projected to grow considerably in the coming years. Recently, several herbal-derived products prescribed in TOM have demonstrated a therapeutic potential for acquired sensorineural hearing loss and tinnitus. Therefore, the aims of this review are to provide a comprehensive overview of the current known efficacy of the herbs used in TOM for preventing different forms of acquired sensorineural hearing loss and tinnitus, and associate the traditional principle with the demonstrated pharmacological mechanisms to establish a solid foundation for directing future research.

METHODS

The present review collected the literature related to herbs used in TOM or related compounds on hearing from Chinese, Korean, and Japanese herbal classics; library catalogs; and scientific databases (PubMed, Scopus, Google Scholar; and Science Direct).

RESULTS

This review shows that approximately 25 herbal species and 40 active compounds prescribed in TOM for hearing loss and tinnitus have shown in vitro or in vivo beneficial effects for acquired sensorineural hearing loss produced by noise, aging, ototoxic drugs or diabetes. The inner ear is highly vulnerable to ischemia and oxidative damage, where several TOM agents have revealed a direct effect on the auditory system by normalizing the blood supply to the cochlea and increasing the antioxidant defense in sensory hair cells. These strategies have shown a positive impact on maintaining the inner ear potential, sustaining the production of endolymph, reducing the accumulation of toxic and inflammatory substances, preventing sensory cell death and preserving sensory transmission. There are still several herbal species with demonstrated therapeutic efficacy whose mechanisms have not been deeply studied and others that have been traditionally used in hearing loss but have not been tested experimentally. In clinical studies, Ginkgo biloba, Panax ginseng, and Astragalus propinquus have demonstrated to improve hearing thresholds in patients with sensorineural hearing loss and alleviated the symptoms of tinnitus. However, some of these clinical studies have been limited by small sample sizes, lack of an adequate control group or contradictory results.

CONCLUSIONS

Current therapeutic strategies have proven that the goal of the traditional oriental medicine principle of increasing bodily fluids is a relevant approach for reducing the development of hearing loss by improving microcirculation in the blood-labyrinth barrier and increasing cochlear blood flow. The potential benefits of TOM agents expand to a multi-target approach on different auditory structures of the inner ear related to increased cochlear blood flow, antioxidant, anti-inflammatory, anti-apoptotic and neuroprotective activities. However, more research is required, given the evidence is very limited in terms of the mechanism of action at the preclinical in vivo level and the scarce number of clinical studies published.

Protective effect of curculigo orchioides extract on cyclophosphamide-induced neurotoxicity in murine model

Free radicals are one of the frequent products of normal cellular metabolism. Disparity of metabolism and excessive generation of free radicals predisposes to disorders like Parkinson's disease, Alzheimer's disease, and aging phenomenon. Curculigo orchioides Gaertn. is known for “adaptogen” and “aphrodisiac” activity and has been proved for antiasthmatic, estrogenic, antiosteoporotic activity along with protection from cisplatin-induced cell damage. C. orchioides was powdered and subjected to soxhlet extraction using methanol. Phytochemical studies and estimation of polyphenols and flavonoids was performed. Acute toxicity studies were performed by Organization for Economic Cooperation and Development OECD guidelines. Animals were treated with cyclophosphamide to induce neurotoxicity. Curculigo orchioides was powdered and subjected to soxhlet extraction using methanol. Catalase, superoxide dismutase, glutathione peroxidase, and lipid peroxidation were estimated by reported methods. C. orchioides (400 mg/kg) significantly promoted restoration of catalase (P < 0.005), superoxide dismutase (P < 0.005), and glutathion (P < 0.05) levels. Similarly, a very significant decrease (P < 0.005) in the levels of malondialdehyde was observed. In all cases as mentioned previously, C. orchioides at dose 200 mg/kg promoted significant (P < 0.05) restoration of enzyme levels. C. orchioides (Kali Musli) is rich source of phytochemicals like flavonoids and polyphenols. Flavonoids and polyphenols are reputed to demonstrate neuroprotective effect. These phytochemicals in the present study might be responsible to demonstrate neuroprotective effect.