Vitamin D Deficiency Promotes Skeletal Muscle Hypersensitivity and Sensory Hyperinnervation
The Journal of Neuroscience, 28 September 2011, 31(39): 13728-13738; doi: 10.1523/JNEUROSCI.3637-11.2011
Abstract: Musculoskeletal pain affects nearly half of all adults, most of whom are vitamin D deficient. Previous findings demonstrated that putative nociceptors (“pain-sensing” nerves) express vitamin D receptors (VDRs), suggesting responsiveness to 1,25-dihydroxyvitamin D. In the present study, rats receiving vitamin D-deficient diets for 2–4 weeks showed mechanical deep muscle hypersensitivity, but not cutaneous hypersensitivity. Muscle hypersensitivity was accompanied by balance deficits and occurred before onset of overt muscle or bone pathology. Hypersensitivity was not due to hypocalcemia and was actually accelerated by increased dietary calcium. Morphometry of skeletal muscle innervation showed increased numbers of presumptive nociceptor axons (peripherin-positive axons containing calcitonin gene-related peptide), without changes in sympathetic or skeletal muscle motor innervation. Similarly, there was no change in epidermal innervation. In culture, sensory neurons displayed enriched VDR expression in growth cones, and sprouting was regulated by VDR-mediated rapid response signaling pathways, while sympathetic outgrowth was not affected by different concentrations of 1,25-dihydroxyvitamin D. These findings indicate that vitamin D deficiency can lead to selective alterations in target innervation, resulting in presumptive nociceptor hyperinnervation of skeletal muscle, which in turn is likely to contribute to muscular hypersensitivity and pain.
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Another important link between essential nutrient deficiency and the development of musculoskeletal pain! This rat-model study was performed to rule out the effect of other conditions that encourage vitamin D deficiency (obesity, sedentary lifestyle, senescence, female and menopausal). It also shows that excess supplementation of calcium may further encourage the development of musculoskeletal pain. Check your vitamin D levels, everyone; if you're deficient and have deep muscle pain, you might reap some rewards by increasing those levels and reducing calcium supplementation if you don't have an acute need for it.
Vitamin D deficiency promotes musculoskeletal pain
Vitamin D deficiency promotes musculoskeletal pain
Age: 26 | Onset Age: 23 | Symptoms: Neuropathic-like pain and hyperalgesia (lateral/anterior thighs mostly, but distributed throughout body); Pain (penis shaft, right side, when erect for long or excess masturbation) | Previous Symptoms: Pain (testicles; penis underside, mostly near base and running up urethra, sharp/burning; perennial region, dull; ejaculatory; post-ejaculatory); Urinary (moderate incomplete voiding; moderate frequency and pain on bladder filling); Sensations (cold in head of penis) | Helped By: Stretching (especially hip rotators and flexors); Yoga (especially lunges, warrior 2, and pigeon) Trigger point release (abdominals; iliopsoas; gluteus muscles and piriformis; bulbospongiosus & ischiocavernosus; thigh adductors); Meditation (mindfulness); Walking & Aerobic Exercise | Worsened By: Stress, anxiety, too much alcohol, lack of sleep, sitting at length | Current prescriptions: nortriptyline (10 mg, 1x at night; for CNS sensitization and IBS) Previous prescriptions: hydroxyzine (10 mg, 1x at night; for urinary symptoms/mast cell stabilization; useful), clonazepam (0.25-0.5 mg, 1x at night; for anxiety/CNS sensitization; useful for short time)