An Evidence-based Review of Medicinal Plants used in Traditional Persian Medicine for Treatment of Osteoarthritis

Antinociceptive and antineuropathic effects of Trifolium resupinatum L. on formalin-induced nociception and cervical spinal cord hemi-contusion: Underlying Mechanisms

ETHNOPHARMACOLOGICAL RELEVANCE

Trifolium resupinatum L. (Fabaceae), known as Persian clover, ethnomedicinally used in Persian folk medicine to treat peritoneal inflammation, rheumatism, and back pain.

AIM OF THE STUDY

To investigate the antineuropathic and antinociceptive activities of Trifolium resupinatum leaves essential oil (TREO) in male Wistar rats, as well as to explore the potential mechanisms of action.

MATERIALS AND METHODS

The antinociceptive activity of TREO and its main constituents, quercetin (Qc) was assessed using the formalin-induced paw licking test. Moreover, the potential mechanisms of antinociception were evaluated through various competitive and non-competitive antagonisms. Additionally, the antineuropathic potential was investigated using the cervical spinal cord hemi-contusion (CCS) model, and the role of phosphorylated Stat-3 was analyzed using Western blotting.

RESULTS

TREO exerted significant antinociceptive activity (P < 0.01) in both phases of the formalin-induced test; however, its effects were more pronounced in the second phase. Modulators of the NO-cGMP-K+ channel pathway significantly reversed the antinociceptive activity of TREO (P < 0.05). Additionally, antagonists of TRPV1 and TRPV2, as well as CB1 and GABAA receptors, significantly reversed the antinociceptive effects of TREO (P < 0.05). In another study, both TREO and Qc significantly attenuated hyperalgesia and mechanical allodynia (P < 0.01) when evaluated using the CCS-induced nociception model. Notably, TREO also reduced the expression levels of interleukin-1 beta, interleukin-2, and tumor necrosis factor alpha in CCS-induced rats (P < 0.05).

CONCLUSION

TREO and Qc exhibit both antinociceptive and anti-neuropathic activities. The antinociceptive effects are partially mediated through the NO-cGMP-K+ channel pathways, along with the activation of TRPV, GABA, and cannabinoid receptors. Furthermore, the anti-neuropathic activity of TREO may be partially regulated through the inhibition of cytokines.

Plant-derived natural medicines for the management of osteoporosis: A comprehensive review of clinical trials

Background

Osteoporosis is a chronic and systemic skeletal disease that is defined by low bone mineral density (BMD) along with an increase in bone fragility and susceptibility to fracture. This study aimed to overview clinical evidence on the use of herbal medicine for management of osteoporosis.

Methods

Electronic databases including Pubmed, Medline, Cochrane library, and Scopus were searched until November 2022 for any clinical studies on the efficacy and/or safety of plant-derived medicines in the management of osteoporosis.

Results

The search yielded 57 results: 19 on single herbs, 16 on multi-component herbal preparations, and 22 on plant-derived secondary metabolites. Risk of fracture, bone alkaline phosphatase, BMD, and specific bone biomarkers are investigated outcomes in these studies. Medicinal plants including Acanthopanax senticosus, Actaea racemosa, Allium cepa, Asparagus racemosus, Camellia sinensis, Cissus quadrangularis, Cornus mas, Nigella sativa, Olea europaea, Opuntia ficus-indica, Pinus pinaster, Trifolium pretense and phytochemicals including isoflavones, ginsenoside, Epimedium prenyl flavonoids, tocotrienols are among plant-derived medicines clinically investigated on osteoporosis. It seems that multi-component herbal preparations were more effective than single-component ones; because of the synergistic effects of their constituents. The investigated herbal medicines demonstrated their promising results in osteoporosis via targeting different pathways in bone metabolism, including balancing osteoblasts and osteoclasts, anti-inflammatory, immunomodulatory, antioxidant, and estrogen-like functions.

Conclusion

It seems that plant-derived medicines have beneficial effects on bone and may manage osteoporosis by affecting different targets and pathways involved in osteoporosis; However, Future studies are needed to confirm the effectiveness and safety of these preparations.

The effect of a topical formulation from Lawsonia inermis L. (henna) on pain intensity in patients with chronic sciatica: A randomized double-blind clinical trial

ETHNOPHARMACOLOGICAL RELEVANCE

Chronic sciatica (CS) is a common condition of disability and pain. Lawsonia inermis L. (henna) is a medicinal plant that is commonly recommended in traditional Persian medicine textbooks for pain relief in patients with sciatica, particularly in the form of oil.

AIM OF THE STUDY

This research was designed to investigate the efficacy of a topical formulation from henna on pain intensity in patients with CS.

METHODS AND MATERIALS

In a randomized, double-blind clinical study, 81 patients were randomly allocated to three groups to receive the topical henna formulation (aqueous extract of henna in sesame oil), sesame oil, or placebo, three times daily, for four weeks. The patients were assessed by visual analog scale (VAS), 36-item short form health survey (SF-36), and Oswestry disability index (ODI).

RESULTS

There was a significant decrease in mean VAS in henna oil compared to sesame oil (p = 0.004) and placebo (p = 0.004). Significant improvements in total SF-36 scores were observed in henna oil and sesame oil compared to placebo (p = 0.011 and p = 0.025, respectively). Furthermore, ODI significantly decreased in henna oil compared to sesame oil (p < 0.001) and placebo (p = 0.005).

CONCLUSION

Henna oil seems to be an effective treatment to reduce pain intensity in patients with CS. Moreover, it improves quality of life and functional ability. Further randomized controlled trials with longer intervention periods are recommended to confirm this efficacy.

Efficacy and safety of oral Nigella sativa oil for symptomatic treatment of knee osteoarthritis: A double-blind, randomized, placebo-controlled clinical trial

BACKGROUND AND PURPOSE

The oil of Nigella sativa (NS) seeds has analgesic and anti-inflammatory effects. Therefore, the efficacy and safety of NS oil in the treatment of knee osteoarthritis were evaluated.

MATERIALS AND METHODS

One hundred and sixteen patients aged 50-70 years were randomly assigned to take 2.5 mL NS oil (N = 58) or placebo (N = 58) orally every 8 h for 1 month. WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) was the primary outcome measure and Visual Analog Scale (VAS) for pain, number of 500 mg acetaminophen tablets taken per day during the trial, patients' satisfaction with the interventions, complete blood count and the blood levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, creatinine and blood urea nitrogen were the secondary outcome measures.

RESULTS

Fifty two and 54 patients respectively in the NS oil and placebo groups completed the study. The VAS scores were decreased by 33.96 ± 17.04% (NS oil group) and 9.21 ± 0.32% (placebo group) (p < 0.001), and WOMAC total scores were decreased by 27.72 ± 18.61% (NS oil group) and 1.34 ± 2.31% (placebo group) (p < 0.001) compared to baseline. The NS oil reduced the dose of acetaminophen significantly compared with the placebo (p = 0.001). The patients were significantly more satisfied with the NS oil than the placebo (p < 0.001). The NS oil had no significant effect on the other variables. There was no side effect.

CONCLUSION

Oral NS oil safely reduces the osteoarthritis symptoms and analgesic dose in the knee osteoarthritis patients.

Natural Approach in Osteoarthritis Therapy

Osteoarthritis (OA) is the most common joint disease worldwide, and its rising prevalence is supported by factors such as obesity and sedentariness. At the molecular level, it is considered an inflammatory disease that leads to the destruction of articular cartilage. Effective therapy to end the degenerative process of arthritis remains elusive, and most therapeutic tools prevent the progress or alleviate the symptoms. By now, medicines for OA are available for oral, topical, or intra-articular (IA) therapy and include analgesics, nonsteroidal anti-inflammatory drugs, corticosteroids, and hyaluronic acid. Compared with conventional oral administration, IA therapy has multiple advantages in terms of bioavailability, efficacy, and toxicity. This review aims to study the underlying beneficial effects of herbal medicine in OA therapy and to open new research perspectives. Herbal medicine administered orally or topically exhibits pharmacological properties that could be relevant for their beneficial effect in OA, mainly anti-inflammatory and antioxidant effects. There are few studies regarding IA injections of plant extracts/ compounds and none related to any combination with agents already used in the clinic. Designing natural pharmaceutical formulations with increased bioavailability that are safe, lack side effects, and are specifically tested, would be a plus for research on medicinal plants and a novelty for the clinic.

Effectiveness of Pistacia atlantica on older adult knee osteoarthritis, a randomized triple blind clinical trial

Osteoarthritis is the most common cause of disability and aging is the major risk factor. One of the low-risk herbal medicines for reducing pain and inflammation in persian medicine is Pistacia atlantica gum. A triple-blind placebo-controlled clinical trial was performed in order to evaluate the efficacy of P. atlantica gum ointment on knee osteoarthritis in elderly people. A total of 60 patients were randomly allocated to two groups. The intervention group used 4% P. atlantica ointment and the control group used placebo, topically applied three times a day, for 8 weeks. The patients were evaluated before and after the intervention using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scale. There were significant differences (p < .001) between two the groups in terms of joint stiffness and pain as well as function. Within groups, regarding the effect size (EF) in joint stiffness was 2.82 and 0.74 in the Pistacia and placebo groups, respectively. Regarding pain, the effect size of the intervention and placebo groups were 3.90 and 0.99, respectively. In addition, regarding function, the effect size of the intervention and the placebo groups were 4.33 and 1.17, respectively. Therefore, it seems that topical P. atlantica is significantly better than the placebo in the old patients with knee osteoarthritis.