In the context of normal cell turnover, apoptosis is a natural phenomenon involved in making essential life and death decisions. Apoptotic pathways balance signals which promote cell death (pro-apoptotic pathways) or counteract these signals (anti-apoptotic pathways). We proposed that changes in anti-apoptotic proteins would occur during mammalian hibernation to aid cell preservation during prolonged torpor under cellular conditions that are highly injurious to most mammals (e.g. low body temperatures, ischemia). Immunoblotting was used to analyze the expression of proteins associated with pro-survival in six tissues of thirteen-lined ground squirrels, Ictidomys tridecemlineatus. The brain showed a concerted response to torpor with significant increases in the levels of all anti-apoptotic targets analyzed (Bcl-2, Bcl-xL, BI-1, Mcl-1, cIAP1/2, xIAP) as well as enhanced phosphorylation of Bcl-2 at S70 and T56. Heart responded similarly with most anti-apoptotic proteins elevated significantly during torpor except for Bcl-xL and xIAP that decreased and Mcl-1 that was unaltered. In liver, BI-1 increased whereas cIAP1/2 decreased. In kidney, there was an increase in BI-1, cIAP and xIAP but decreases in Bcl-xL and p-Bcl-2(T56) content. In brown adipose tissue, protein levels of BI-1, cIAP1/2, and xIAP decreased significantly during torpor (compared with euthermia) whereas Bcl-2, Bcl-xL, Mcl-1 were unaltered; however, Bcl-2 showed enhanced phosphorylation at Thr56 but not at Ser70. In skeletal muscle, only xIAP levels changed significantly during torpor (an increase). The data show that anti-apoptotic pathways have organ-specific responses in hibernators with a prominent potential role in heart and brain where coordinated enhancement of anti-apoptotic proteins occurred in response to torpor.

To avoid the harsh conditions of winter climates, hibernating mammals undergo a systematic depression of physiological function by reducing their metabolic rate. During this process, hibernators are exposed to significant stresses (e.g., low body temperature, ischemia-reperfusion) that must be dealt with appropriately to avoid irreversible tissue damage. Consequently, we investigated the contribution of stress-responsive antioxidant enzymes, heat shock proteins, signal transduction pathways (e.g., mitogen-activated protein kinases, MAPK), and transcription factors for their role in conferring tolerance to stress in the hibernating thirteen-lined ground squirrel (Ictidomys tridecemlineatus). Using a combination of multiplex protein panels and traditional immunoblotting procedures, we have focused on these stress factors in brown adipose tissue (BAT) and white adipose tissue (WAT) over cycles of torpor-arousal since they provide the means for heat production as a result of non-shivering thermogenesis and the mobilization of critical energy reserves, respectively. We show the differential and tissue-specific regulation of stress factors including a unified upregulation of the antioxidant enzyme Thioredoxin 1 in both tissues, an upregulation of superoxide dismutase (SOD1 and SOD2) in WAT, and an increase in heat shock proteins during the transitory periods of the torpor-arousal cycle (HSP90α in BAT and HSP60 in WAT). Additionally, an upregulation of the active form of ERK1/2 and p38 in BAT and select transcription factors (e.g., CREB-1 and ELK-1) in both tissues were identified. These data provide us with greater insight into the molecular mechanisms responsible for this animal's natural stress tolerance and outline molecular signatures which define stress resistance.

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Objective To determine the proportion of chronic low back pain patients who achieve a clinically meaningful response from different pharmacologic and nonpharmacologic treatments.Data sources MEDLINE, EMBASE, Cochrane Library, and gray literature search. Study selectionPublished randomized controlled trials (RCTs) that reported a responder analysis of adults with chronic low back pain treated with any of the following 15 interventions: oral or topical nonsteroidal antiinflammatory drugs (NSAIDs), exercise, acupuncture, spinal manipulation therapy, corticosteroid injections, acetaminophen, oral opioids, anticonvulsants, tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors (SNRIs), selective serotonin reuptake inhibitors, cannabinoids, oral muscle relaxants, or topical rubefacients.Synthesis A total of 63 RCTs were included. There was moderate certainty that exercise (risk ratio [RR] of 1.71; 95% CI 1.37 to 2.15; number needed to treat [NNT] of 7), oral NSAIDs (RR = 1.44; 95% CI 1.17 to 1.78; NNT = 6), and SNRIs (duloxetine; RR = 1.25; 95% CI 1.13 to 1.38; NNT = 10) provide clinically meaningful benefits to patients with chronic low back pain. Exercise was the only intervention with sustained benefit (up to 48 weeks). There was low certainty that spinal manipulation therapy and topical rubefacients benefit patients. The benefit of acupuncture disappeared in higher-quality, longer (> 4 weeks) trials. Very low-quality evidence demonstrated that corticosteroid injections are ineffective. Patients treated with opioids had a greater likelihood of discontinuing treatment owing to an adverse event (number needed to harm of 5) than continuing treatment to derive any clinically meaningful benefit (NNT = 16), while those treated with SNRIs (duloxetine) had a similar likelihood of continuing treatment to attain benefit (NNT = 10) as those discontinuing the medication owing to an adverse event (number need to harm of 11). One trial each of anticonvulsants and topical NSAIDs found similar benefit to that of placebo. No RCTs of acetaminophen, cannabinoids, muscle relaxants, selective serotonin reuptake inhibitors, or tricyclic antidepressants met the inclusion criteria.} Findings of this systematic review were used to develop a clinical decision aid (page 32). This systematic review is one in a series that will inform guidelines on pain treatment in primary care.

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et al. Subcutaneous injection of testosterone is an effective and preferred alternative to intramuscular injection: demonstration in female-to-male transgender patients.

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