Dr. Weeks’ Comment: Thymoquinone (TQ) is a compound in black cumin seed – the major ingredient in SOUL. The science behind these potent ingredients in SOUL (black cumin seed, black raspberry seed, Chardonnay grape seed, and the two 5 carbon sweeteners – D-Ribose and Xylitol) underscore the importance of including potent herbs and seeds in one’s diet.
“…TQ was believed to exert anti-inflammatory effects by inhibiting the synthesis of prostaglandins and leukotrienes which are the main mediators of inflammation…”
Nigella Sativa reverses osteoporosis in ovariectomized rats
Ansam Aly Seif
BMC Complementary and Alternative Medicine 2014, 14:22 doi:10.1186/1472-6882-14-22
Osteoporosis poses a significant public health issue. It is a skeletal disorder characterized by compromised bone strength that predisposes to increased risk of fracture. There is a direct relationship between the lack of estrogen after menopause and the development of osteoporosis. About 33% of women over 50 will experience bone fractures as a result of osteoporosis. Nigella Sativa (NS) has been shown to have beneficial effects on bone and joint diseases. The present study was conducted to elucidate the protective effect of Nigella Sativa on osteoporosis produced by ovariectomy in rats.
Besides that, previous literatures on NS and TQ have highlighted two properties that might be responsible for their antiosteoporotic effects, that is, antoxidative and antiinflammatory properties . Histological examination of liver specimens showed mononuclear cellular infiltration and congested blood vessels in OVX-NS rats. Recently, plenty of evidences had surfaced, linking inflammation to osteoporosis. This has led to the opinions that inflammation may contribute to osteoporosis . Kireev et al. , reported that pro-inflammatory cytokines TNF-alpha (TNF- α), IL-1beta and IL-6 measured in liver homogenates were significantly increased and anti-inflammatory IL-10 decreased during ageing and after ovariectomy in rats. Moreover, Levels of lipid peroxides in the liver homogenates as well as iNOS protein expression and NO levels were increased in old rats as compared to young animals; this effect was more evident in ovariectomized animals. The authors also stated that administration of the different hormonal replacement therapies was able to inhibit the induction of pro-inflammatory cytokines and iNOS, decreased the levels of oxidative stress markers and had therapeutic potential in the prevention of liver injury. Moreover, Pighon et al. , showed that exercise training in ovariectomized rats acted like estrogen in properly regulating the expression of inflammatory biomarkers in liver of OVX rats. TQ was believed to exert anti-inflammatory effects by inhibiting the synthesis of prostaglandins and leukotrienes which are the main mediators of inflammation . The results of the present study show significant elevation of plasma nitrates, NO surrogate, in OVX rats compared to SHAM rats, which was lowered to control levels by NS supplementation in OVX-NS group. NO might have been produced by macrophages as one of the inflammatory signs that were corrected by NS supplementation. These results are in agreement with Suna et al. , who stated that a possible anti-inflammatory mechanism of TQ might be suppression of nitric oxide production by macrophages. Another study has shown that the alveolar bone loss due to periodontitis was reduced by gastric feeding of TQ to rats. This was accompanied by reduction in osteoclast number and raised osteoblastic activity in TQ-treated rats . In studies using rheumatoid arthritis model, TQ was reported to reduce the serum levels of IL-1 and TNF-α,. The production of cytokines including TNF and IL-17 can increase osteoclastogenesis and bone loss in inflammatory liver conditions . Bone protective effects of estrogen might involve suppression of inflammatory cytokines such as IL-1 and TNF-α, which in turn activate inducible NO synthase (iNOS). iNOS is only expressed in response to inflammatory stimuli, and NO derived from this pathway potentiates cytokine and inflammatory-induced bone loss . This might be a possible explanation for the detected significant increase in plasma nitrates level in OVX rats in the present study. Furthermore, a previous study reported that IL-1 and TNF-α were increased in healthy premenopausal women who underwent ovariectomy and reached the highest levels 8 weeks after ovariectomy, and these changes were associated with indices of bone resorption . In the present study, the anti-inflammatory effects of NS were further assured by the significant decrease in plasma TNF-α and plasma IL-6 levels in the OVX-NS group compared to the OVX group.
Osteoporotic patients were found to be under oxidative stress as their lipid peroxidation levels were elevated and antioxidant enzymes reduced [33,34]. Most risk factors for osteoporosis were associated with oxidative stress such as hypertension , diabetes mellitus , and smoking . Reactive oxygen species could also stimulate osteoclast formation and activity , impair osteoblastic function , and decrease osteoblast recruitment and collagen synthesis . Exposure to oxidative stress would result in reduction of bone-mineral density . Increased oxidative stress could be attributed to the loss of the antioxidant effects of estrogen . Since it is apparent that oxidative stress may lead to osteoporosis, antioxidants may play a role in protecting bone against the damaging effects of free-radicals. It has been reported that the free radical scavenging capability of TQ is as effective as superoxide dismutase . It is most effective in scavenging superoxides, the reactive oxygen species which plays an important role in the activation of osteoclasts . The results of the present study are in agreement with the previous data showing that plasma MDA levels, an important measure of lipid peroxidation, were significantly increased in OVX rats compared to both SHAM and OVX-NS rats.
It can be concluded that NS has shown potential as a safe and effective antiosteoporotic agent, which can be attributed to its high content of unsaturated fatty acids as well as its antioxidant and anti-inflammatory properties.