Mechanisms of action of vitamin B1 (thiamine), B6 (pyridoxine), and B12 (cobalamin) in pain: a narrative review.

Pain is a complex sensory and emotional experience with nociceptive, nociplastic, and neuropathic components. An involvement of neurotropic B vitamins (B1 - thiamine, B6 - pyridoxine, and B12 - cyanocobalamin) as modulators of inflammation and pain has been long discussed. New evidence suggests their therapeutic potential in different pain conditions. In this review, we discuss the main role of neurotropic B vitamins on different nociceptive pathways in the nervous system and to describe their analgesic action mechanisms. The performed literature review showed that, through different mechanisms, these vitamins regulate several inflammatory and neural mediators in nociceptive and neuropathic pain. Some of these processes include aiming the activation of the descending pain modulatory system and in specific intracellular pathways, anti-inflammatory, antioxidative and nerve regenerative effects. Moreover, recent data shows the antinociceptive, antiallodynic, and anti-hyperalgesic effects of the combination of these vitamins, as well as their synergistic effects with known analgesics. Understanding how vitamins B1, B6, and B12 affect several nociceptive mechanisms can therefore be of significance in the treatment of various pain conditions.

Tools for comprehensive evaluation of sexual function in patients with multiple sclerosis.

INTRODUCTION: Multiple sclerosis (MS) is a demyelinating disease of the central nervous system (CNS) that affects young adults, causing a variety of symptoms (motor alterations, visual alterations, loss of sphincter control, gait alterations) that impair the patient's functional status. However, other symptoms, such as sexual dysfunction, can also have an effect on quality of life. DEVELOPMENT: Sexual dysfunction can occur at any time during the course of the disease; its prevalence varies between 50% and 90%, and it can be secondary to demyelinating lesions in the spinal cord and/or brain or caused by symptoms that do not directly involve the nervous system (fatigue; psychological, social, and cultural factors; etc.). Although its prevalence and impact on quality of life are well known, sexual dysfunction is still frequently underestimated. Therefore, in this article we review the different scales for assessing presence or severity of sexual dysfunction, in order to offer early multidisciplinary management. CONCLUSION: We evaluated 5 questionnaires that could identify the presence of sexual dysfunction in patients with MS and determine its aetiology, assisting in treatment decision making. MS must be understood as a complex disease that encompasses and compromises different aspects of patients' health, and goes beyond simply measuring disability.

[Role of B vitamins, thiamine, pyridoxine, and cyanocobalamin in back pain and other musculoskeletal conditions: a narrative review]. / Papel de las vitaminas B, tiamina, piridoxina y cianocobalamina en el dolor de espalda y otras condiciones musculoesqueléticas: revisión narrativa.

Low back pain, as well as other musculoskeletal disorders (neck pain, osteoarthritis, etc.), are a very frequent cause of consultation both in primary care and in other hospital specialties and are usually associated with high functional and work disability. Acute low back pain can present different nociceptive, neuropathic and nonciplastic components, which leads to consider it as a mixed type pain. The importance of the concept of mixed pain is due to the fact that the symptomatic relief of these pathologies requires a multimodal therapeutic approach to various pharmacological targets. The antinociceptive role of the B vitamin complex has been recognized for several decades, specifically the combination of Thiamine, Pyridoxine and Cyanocobalamin (TPC). Likewise, there is accumulated evidence that indicates an adjuvant analgesic action in low back pain. The aim of the present review is to present the existing evidence and the latest findings on the therapeutic effects of the TPC combination in low back pain. Likewise, some of the most relevant mechanisms of action involved that can explain these effects are analyzed. The reviewed evidence indicates that the combined use of PCT has an adjuvant analgesic effect in mixed pain, specifically in low back pain and other musculoskeletal disorders with nociceptive and neuropathic components. This effect can be explained by an anti-inflammatory, antinociceptive, neuroprotective and neuromodulatory action of the TPC combination on the descending pain system.

Tools for comprehensive evaluation of sexual function in patients with multiple sclerosis. / Herramientas para la evaluación integral de la función sexual en pacientes con esclerosis múltiple.

INTRODUCTION: Multiple sclerosis (MS) is a demyelinating disease of the central nervous system (CNS) that affects young adults, causing a variety of symptoms (motor alterations, visual alterations, loss of sphincter control, gait alterations) that impair the patient's functional status. However, other symptoms, such as sexual dysfunction, can also have an effect on quality of life. DEVELOPMENT: Sexual dysfunction can occur at any time during the course of the disease; its prevalence varies between 50% and 90%, and it can be secondary to demyelinating lesions in the spinal cord and/or brain or caused by symptoms that do not directly involve the nervous system (fatigue; psychological, social, and cultural factors; etc.). Although its prevalence and impact on quality of life are well known, sexual dysfunction is still frequently underestimated. Therefore, in this article we review the different scales for assessing presence or severity of sexual dysfunction, in order to offer early multidisciplinary management. CONCLUSION: We evaluated 5 questionnaires that could identify the presence of sexual dysfunction in patients with MS and determine its aetiology, assisting in treatment decision making. MS must be understood as a complex disease that encompasses and compromises different aspects of patients' health, and goes beyond simply measuring disability.