Prophylactic administration of an extract from Plantaginis Semen and its major component aucubin inhibits mechanical allodynia caused by paclitaxel in mice

Antinociceptive effect of plant-based natural products in chemotherapy-induced peripheral neuropathies: A systematic review

Chemotherapy-induced peripheral neuropathy (CIPN) is one of the most prevalent and difficult-to-treat symptoms in cancer patients. For this reason, the explore for unused helpful choices able of filling these impediments is essential. Natural products from plants stand out as a valuable source of therapeutic agents, being options for the treatment of this growing public health problem. Therefore, the objective of this study was to report the effects of natural products from plants and the mechanisms of action involved in the reduction of neuropathy caused by chemotherapy. The search was performed in PubMed, Scopus and Web of Science in March/2021. Two reviewers independently selected the articles and extracted data on characteristics, methods, study results and methodological quality (SYRCLE). Twenty-two studies were selected, describing the potential effect of 22 different phytochemicals in the treatment of CIPN, with emphasis on terpenes, flavonoids and alkaloids. The effect of these compounds was demonstrated in different experimental protocols, with several action targets being proposed, such as modulation of inflammatory mediators and reduction of oxidative stress. The studies demonstrated a predominance of the risk of uncertain bias for randomization, baseline characteristics and concealment of the experimental groups. Our findings suggest a potential antinociceptive effect of natural products from plants on CIPN, probably acting in several places of action, being strategic for the development of new therapeutic options for this multifactorial condition.

Therapeutics for Chemotherapy-Induced Peripheral Neuropathy: Approaches with Natural Compounds from Traditional Eastern Medicine

Chemotherapy-induced peripheral neuropathy (CIPN) often develops in patients with cancer treated with commonly used anti-cancer drugs. The symptoms of CIPN can occur acutely during chemotherapy or emerge after cessation, and often accompany long-lasting intractable pain. This adverse side effect not only affects the quality of life but also limits the use of chemotherapy, leading to a reduction in the survival rate of patients with cancer. Currently, effective treatments for CIPN are limited, and various interventions are being applied by clinicians and patients because of the unmet clinical need. Potential approaches to ameliorate CIPN include traditional Eastern medicine-based methods. Medicinal substances from traditional Eastern medicine have well-established analgesic effects and are generally safe. Furthermore, many substances can also improve other comorbid symptoms in patients. This article aims to provide information regarding traditional Eastern medicine-based plant extracts and natural compounds for CIPN. In this regard, we briefly summarized the development, mechanisms, and changes in the nervous system related to CIPN, and reviewed the substances of traditional Eastern medicine that have been exploited to treat CIPN in preclinical and clinical settings.

Spiky titanium dioxide nanoparticles-loaded Plantaginis Semen polysaccharide as an adjuvant to enhance immune responses

The purpose of this study was to prepare spiky titanium dioxide nanoparticles-loaded Plantaginis Semen polysaccharide (SN-TiO₂-PSP), and the structural characterization and immune response of infectious laryngotracheitis (ILT) vaccine in Hetian chickens were investigated. The structural characterization of SN-TiO₂-PSP was analyzed by FT-IR, TEM, and TGA analysis. And the immune organs indexes, lymphocytes proliferation, specific antibody levels, and ratios of CD4⁺ and CD8⁺ T lymphocytes were studied. Structural characterization results showed that SN-TiO₂-PSP has a typical polysaccharide absorption peak and good stability. The SN-TiO₂-PSP's shape was similar to sea urchin, and its zeta potential and particle size were 27.56 mV and 976.11 nm, respectively. In vivo results showed that SN-TiO₂-PSP could enhance the proliferation of peripheral lymphocytes, specific antibody levels, CD4⁺ and CD8⁺ T lymphocytes ratios, IL-4 and INF-γ levels in Hetian chickens vaccinated with ILT vaccine on D₇, D₁₄, D₂₁, and D₂₈. In addition, SN-TiO₂-PSP not only enhanced the indexes of immune organs but also promoted the development of immune organs. Therefore, SN-TiO₂-PSP has immune adjuvant activity and may become a new potential immune adjuvant.

Preclinical and Clinical Evidence of Therapeutic Agents for Paclitaxel-Induced Peripheral Neuropathy

Paclitaxel is an essential drug in the chemotherapy of ovarian, non-small cell lung, breast, gastric, endometrial, and pancreatic cancers. However, it frequently causes peripheral neuropathy as a dose-limiting factor. Animal models of paclitaxel-induced peripheral neuropathy (PIPN) have been established. The mechanisms of PIPN development have been elucidated, and many drugs and agents have been proven to have neuroprotective effects in basic studies. In addition, some of these drugs have been validated in clinical studies for their inhibitory PIPN effects. This review summarizes the basic and clinical evidence for therapeutic or prophylactic effects for PIPN. In pre-clinical research, many reports exist of neuropathy inhibitors that target oxidative stress, inflammatory response, ion channels, transient receptor potential (TRP) channels, cannabinoid receptors, and the monoamine nervous system. Alternatively, very few drugs have demonstrated PIPN efficacy in clinical trials. Thus, enhancing translational research to translate pre-clinical research into clinical research is important.

Iridoids isolated from Viticis Fructus inhibit paclitaxel-induced mechanical allodynia in mice

Chemotherapy-induced peripheral neuropathy (CIPN) manifests as mechanical allodynia and hyperalgesia, and is one of the main adverse effects of chemotherapeutic agents. Currently available therapeutic drugs are not sufficiently effective for the management of this adverse effect in the clinic. Therefore, the development of novel therapeutic agents for treating CIPN is necessary. Our previous study suggested the potential of aucubin and pedicularis-lactone (1) as active compounds responsible for the anti-allodynic property of Plantaginis Semen. However, the activity of purified 1 has not been evaluated due to its low content in Plantaginis Semen. In the present study, 1 was isolated from Viticis Fructus, as well as viteoid I (2) and viteoid II (3) during the process of isolation. The purities of isolated 1, 2, and 3 were determined as 67.15%, 92.12%, and 86.72%, respectively, by quantitative ¹H-NMR, using DSS-d₆ as an internal standard. Repeated daily oral administration of these three iridoids at a dose of 15 mg/kg significantly inhibited the PTX-induced mechanical allodynia in mice, suggesting the anti-allodynic activities of 1, 2, and 3. This study provides confirmatory evidence for the anti-allodynic activity of purified 1 and also reveals two additional active iridoids from Viticis Fructus. These three iridoids could be potential candidates for the treatment of CIPN.

Search of anti-allodynic compounds from Plantaginis Semen, a crude drug ingredient of Kampo formula "Goshajinkigan"

Chemotherapy-induced peripheral neuropathy (CIPN) is one of the dose-limiting side effects of cancer chemotherapy. Although the control of CIPN is important, it is difficult to manage with currently available therapeutic drugs. Therefore, there is a need for novel therapeutic agents for treating CIPN. Goshajinkigan (GJG) is a Kampo formula composed of ten crude drugs. While GJG has been used for the treatment of CIPN, the active constituents of GJG and their underlying mechanisms of pharmacological effects are still unknown. Our previous study revealed that repetitive oral administration of the water extract of Plantaginis Semen, a crude drug ingredient of GJG, inhibited the mechanical allodynia induced by an intraperitoneal injection of paclitaxel in mice. To elucidate the active compounds of Plantaginis Semen, activity-guided separation of the water extract of Plantaginis Semen was performed. From the active fraction, four iridoids (1-4) were identified. Repetitive oral administration of aucubin (1) at 100 or 30 mg/kg and 100 mg/kg of the fraction crude 3 [primarily comprised of pedicularis-lactone (3)], showed anti-allodynic activity, suggesting 1 and 3 could be some of the active compounds responsible for the anti-allodynic property of Plantaginis Semen and GJG. Our study establishes that oral administration of 1 has potent anti-allodynic effect in addition to the activity of intraperitoneally administered 1 reported previously. Identification of active anti-allodynic compounds found in Kampo formulations will support the development of novel therapies for the management of CIPN in cancer patients.

Medicinal plants and their isolated phytochemicals for the management of chemotherapy-induced neuropathy: therapeutic targets and clinical perspective

BACKGROUND

Chemotherapy, as one of the main approaches of cancer treatment, is accompanied with several adverse effects, including chemotherapy-induced peripheral neuropathy (CIPN). Since current methods to control the condition are not completely effective, new treatment options should be introduced. Medicinal plants can be suitable candidates to be assessed regarding their effects in CIPN. Current paper reviews the available preclinical and clinical studies on the efficacy of herbal medicines in CIPN.

METHODS

Electronic databases including PubMed, Scopus, and Cochrane library were searched with the keywords "neuropathy" in the title/abstract and "plant", "extract", or "herb" in the whole text. Data were collected from inception until April 2018.

RESULTS

Plants such as chamomile (Matricaria chamomilla L.), sage (Salvia officinalis L.), cinnamon (Cinnamomum cassia (L.) D. Don), and sweet flag (Acorus calamus L.) as well as phytochemicals like matrine, curcumin, and thioctic acid have demonstrated beneficial effects in animal models of CIPN via prevention of axonal degeneration, decrease in total calcium level, improvement of endogenous antioxidant defense mechanisms such as superoxide dismutase and reduced glutathione, and regulation of neural cell apoptosis, nuclear factor-ĸB, cyclooxygenase-2, and nitric oxide signaling. Also, five clinical trials have evaluated the effect of herbal products in patients with CIPN.

CONCLUSIONS

There are currently limited clinical evidence on medicinal plants for CIPN which shows the necessity of future mechanistic studies, as well as well-designed clinical trial for further confirmation of the safety and efficacy of herbal medicines in CIPN. Graphical abstract Schematic mechanisms of medicinal plants to prevent chemotherapy-induced neuropathy: NO: nitric oxide, TNF: tumor necrosis factor, PG: prostaglandin, NF-ĸB: nuclear factor kappa B, LPO: lipid peroxidation, ROS: reactive oxygen species, COX: cyclooxygenase, IL: interleukin, ERK: extracellular signal-related kinase, X: inhibition, ↓: induction.

Plantago asiatica Seed Extracts Alleviated Blood Pressure in Phase I⁻Spontaneous Hypertension Rats

Arterial pressure of each new breeding spontaneous Phase-1 hypertension (P1-HT) rat was recorded for 5 min by intravascular femoral artery catheter that served as a reference value prior to treatment. In the acute antihypertensive test, 0.36 g/kg Bwt of Plantago asiatica seed extract (PSE) was administered, via gavage feeding, to P1-HT rats, and the arterial pressures were continuously recorded for 1 h. The acute antihypertensive effects of PSE on P1-HT rats appeared within 15 min after PSE administration and lasted over 1 h with systolic pressure decreased 31.5 mmHg and diastolic pressure decreased 18.5 mmHg. The systolic pressure decreased 28 mmHg and diastolic pressure decreased 16 mmHg in P1-HT rats when simultaneously compared with verapamil hydrochloride (reference drug), whereas there were no significant differences in the pretreated reference values of acute PSE treatment and the untreated control. In the chronic test, P1-HT rats received 0.36 g/kg Bwt day of PSE or equal volume of water for 4 weeks via oral gavage, and the lower blood pressure tendencies of chronic PSE treatment were also found when compared with the controls. The antihypertensive values of PSE were also confirmed in spontaneously hypertensive rats (SHRs). Oral administration with PSE can effectively moderate blood pressure within an hour, while taking PSE daily can control the severity of hypertension, suggesting PSE is a potentially antihypertensive herb.

Goshajinkigan for prevention of chemotherapy-induced peripheral neuropathy: a systematic review and meta-analysis

PURPOSE

Chemotherapy-induced peripheral neuropathy (CIPN) limits the dose of chemotherapy and reduces patients' quality of life. Goshajinkigan is a Japanese herbal medicine used to alleviate neuropathy and general pain. A clinical guideline for prevention and management of CIPN stated that the prophylactic efficacy of goshajinkigan against CIPN was inconclusive. We conducted a systematic review to examine whether goshajinkigan prevents CIPN in patients receiving neurotoxic chemotherapy.

METHODS

We searched PubMed, EMBASE, Ichushi, and the Cochrane Central Register of Controlled Trials for eligible trials. Randomized controlled trials that examined the efficacy and safety of goshajinkigan for prevention of CIPN were included. Our primary outcomes were incidence of CIPN, response to chemotherapy, and adverse effects. We pooled data using a random effects model.

RESULTS

We analyzed five trials involving a total of 397 patients. When evaluated with Neurotoxicity Criteria of Debiopharm, goshajinkigan was associated with reduced incidence of CIPN of grade ≥ 1 (risk ratio [RR] 0.43; 95% CI, 0.27 to 0.66) and grade 3 (RR 0.42; 95% CI, 0.25 to 0.71), but this beneficial association was not found for grade ≥ 2 of CIPN. Goshajinkigan was not associated with reduced incidence of CIPN when assessed with the National Cancer Institute Common Terminology Criteria for Adverse Events, or improved response to chemotherapy. Goshajinkigan was well tolerated based on one trial.

CONCLUSIONS

Goshajinkigan is unlikely to prevent CIPN in patients undergoing neurotoxic chemotherapy. Given the low quality and insufficient amount of the evidence, use of goshajinkigan as standard of care is not currently recommended.

Prophylactic Administration of Aucubin Inhibits Paclitaxel-Induced Mechanical Allodynia via the Inhibition of Endoplasmic Reticulum Stress in Peripheral Schwann Cells

Paclitaxel is a chemotherapeutic agent that causes peripheral neuropathy as its major dose-limiting side effect. However, the peripheral neuropathy is difficult to manage. A study we recently conducted showed that repetitive administration of aucubin as a prophylactic inhibits paclitaxel-induced mechanical allodynia. However, the mechanisms underlying the anti-allodynic activity of aucubin, which is a major component of Plantaginis Semen, was unclear. In addition to mechanical allodynia, aucubin inhibited spontaneous and mechanical stimuli-induced firing in spinal dorsal horn neurons; however, catalpol, a metabolite of aucubin, did not show these effects. Furthermore, paclitaxel induced the expression of CCAAT/enhancer-binding protein homologous protein, a marker of endoplasmic reticulum (ER) stress, in the sciatic nerve and a Schwann cell line (LY-PPB6 cells); however, this effect was inhibited by aucubin. These results suggest that aucubin inhibits paclitaxel-induced mechanical allodynia through the inhibition of ER stress in peripheral Schwann cells.

Potential application of the Kampo medicine goshajinkigan for prevention of chemotherapy-induced peripheral neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is one of the most common and severe adverse effects related to cancer treatment. Unfortunately, although several agents and protocols have been proposed, no prophylactic strategies have yet to be proven useful. Therefore, new alternative therapies have been considered for CIPN prevention. Herbal medicine in Japan, called Kampo medicine, is derived from traditional Chinese medicine. Goshajinkigan (GJG) is a Kampo medicine, that is comprised of ten herbs. The aim of this work is to analyse the results of pre-clinical and clinical studies on the potential applications of GJG in CIPN prevention.