Carlo Serra

Testosterone Plus Low-Intensity Physical Training in Late Life Improves Functional Performance, Skeletal Muscle Mitochondrial Biogenesis, and Mitochondrial Quality Control in Male Mice

Testosterone supplementation increases muscle mass in older men but has not been shown to consistently improve physical function and activity. It has been hypothesized that physical exercise is required to induce the adaptations necessary for translation of testosterone-induced muscle mass gain into functional improvements. However, the effects of testosterone plus low intensity physical exercise training (T/PT) on functional performance and bioenergetics are unknown. In this pilot study, we tested the hypothesis that combined administration of T/PT would improve functional performance and bioenergetics in male mice late in life more than low-intensity physical training alone. 28-month old male mice were randomized to receive T/PT or vehicle plus physical training (V/PT) for 2 months. Compare to V/PT control, administration of T/PT was associated with improvements in muscle mass, grip strength, spontaneous physical movements, and respiratory activity. These changes were correlated with increased mitochondrial DNA copy number and expression of markers for mitochondrial biogenesis. Mice receiving T/PT also displayed increased expression of key elements for mitochondrial quality control, including markers for mitochondrial fission-and-fusion and mitophagy. Concurrently, mice receiving T/PT also displayed increased expression of markers for reduced tissue oxidative damage and improved muscle quality. Conclusion: Testosterone administered with low-intensity physical training improves grip strength, spontaneous movements, and respiratory activity. These functional improvements were associated with increased muscle mitochondrial biogenesis and improved mitochondrial quality control.

Pituitary surgery and volumetric assessment of extent of resection: a paradigm shift in the use of intraoperative magnetic resonance imaging

OBJECTIVE The aim of this study was to quantitatively assess the role of intraoperative high-field 3-T MRI (3T-iMRI) in improving the gross-total resection (GTR) rate and the extent of resection (EOR) in endoscopic transsphenoidal surgery (TSS) for pituitary adenomas. METHODS Radiological and clinical data from a prospective database were retrospectively analyzed. Volumetric measurements of adenoma volumes pre-, intraoperatively, and 3 months postoperatively were performed in a consecutive series of patients who had undergone endoscopic TSS. The quantitative contribution of 3T-iMRI was measured as a percentage of the additional rate of GTR and of the EOR achieved after 3T-iMRI. RESULTS The cohort consisted of 50 patients (51 operations) harboring 33 nonfunctioning and 18 functioning pituitary adenomas. Mean adenoma diameter and volume were 21.1 mm (range 5-47 mm) and 5.23 cm(3) (range 0.09-22.14 cm(3)), respectively. According to Knosps classification, 10 cases were Grade 0; 8, Grade 1; 17, Grade 2; 12, Grade 3; and 4, Grade 4. Gross-total resection was the surgical goal (targeted [t]GTR) in 34 of 51 operations and was initially achieved in 16 (47%) of 34 at 3T-iMRI and in 30 (88%) of 34 cases after further resection. In this subgroup, the EOR increased from 91% at 3T-iMRI to 99% at the 3-month MRI (p < 0.05). In the 17 cases in which subtotal resection (STR) had been planned (tSTR), the EOR increased from 79% to 86% (p < 0.05) and GTR could be achieved in 1 case. Intrasellar remnants were present in 20 of 51 procedures at 3T-iMRI and in only 5 (10%) of 51 procedures after further resection (median volume 0.15 cm(3)). Overall, the use of 3T-iMRI led to further resection in 27 (53%) of 51 procedures and permitted GTR in 15 (56%) of these 27 procedures; thus, the GTR rate in the entire cohort increased from 31% (16 of 51) to 61% (31 of 51) and the EOR increased from 87% to 95% (p < 0.05). CONCLUSIONS The use of high-definition 3T-iMRI allowed precise visualization and quantification of adenoma remnant volume. It helped to increase GTR and EOR rates in both tGTR and tSTR patient groups. Moreover, it helped to achieve low rates of intrasellar remnants. These data support the use of 3T-iMRI to achieve maximal, safe adenoma resection.

The Effects of a Single Developmentally Entrained Pulse of Testosterone in Female Neonatal Mice on Reproductive and Metabolic Functions in Adult Life

Early postnatal exposures to sex steroids have been well recognized to modulate predisposition to diseases of adulthood. There is a complex interplay between timing, duration and dose of endocrine exposures through environmental or dietary sources that may alter the sensitivity of target tissues to the exogenous stimuli. In this study, we determined the metabolic and reproductive programming effects of a single developmentally entrained pulse of testosterone (T) given to female mice in early postnatal period. CD-1 female mice pups were injected with either 5 μg of T enanthate (TE) or vehicle (control [CON] group) within 24 hours after birth and followed to adult age. A total of 66% of T-treated mice exhibited irregular cycling, anovulatory phenotype, and significantly higher ovarian weights than vehicle-treated mice. Longitudinal nuclear magnetic resonance measurements revealed that TE group had greater body weight, whole-body lean, and fat mass than the CON group. Adipose tissue cellularity analysis in TE group revealed a trend toward higher size and number than their littermate CONs. The brown adipose tissue of TE mice exhibited white fat infiltration with down-regulation of several markers, including uncoupling protein 1 (UCP-1), cell death-inducing DNA fragmentation factor, α-subunit-like effector A, bone morphogenetic protein 7 as well as brown adipose tissue differentiation-related transcription regulators. T-injected mice were also more insulin resistant than CON mice. These reproductive and metabolic reprogramming effects were not observed in animals exposed to TE at 3 and 6 weeks of age. Collectively, these data suggest that sustained reproductive and metabolic alterations may result in female mice from a transient exposure to T during a narrow postnatal developmental window.

Rapid and Accurate Anatomical Localization of Implanted Subdural Electrodes in a Virtual Reality Environment

BACKGROUND An accurate and rapid anatomical localization of implanted subdural electrodes is essential in the invasive diagnostic process for epilepsy surgery. OBJECTIVE To demonstrate our experience with a three-dimensional (3D) virtual reality simulation software (Dextroscope®, Bracco Imaging, Milano, Italy) in the postoperative localization of subdural electrodes. METHODS Postoperative thin-slice computed tomography (CT) scans were coregistered to preoperative 3D magnetic resonance (MR) images in the Dextroscope environment in 10 patients. Single-electrode contacts were segmented and their positions in relation to specific brain anatomic structures were obtained by 3D reconstruction within the Dextroscope environment. The spatial accuracy was tested by comparing the positions of the electrode contacts as visible in the 3D reconstruction with intraoperative photographs. Image processing time was also recorded. RESULTS The 3D stereoscopic reconstruction provided an accurate representation of the implanted electrodes with highly detailed visualization of the underlying anatomy. The mean absolute difference between 3D reconstruction and intraoperative photographs was 2.4 mm ± 2.2 mm. The processing time to obtain the 3D reconstructions did not exceed 15 minutes. CONCLUSIONS The results indicate that the 3D virtual reality simulation software used in our series is a useful tool for rapid and precise localization of subdural electrodes implanted for invasive electroencephalography (EEG) recordings.

The Effects of Short-Term and Long-Term Testosterone Supplementation on Blood Viscosity and Erythrocyte Deformability in Healthy Adult Mice

Testosterone treatment induces erythrocytosis that could potentially affect blood viscosity and cardiovascular risk. We thus investigated the effects of testosterone administration on blood viscosity and erythrocyte deformability using mouse models. Blood viscosity, erythrocyte deformability, and hematocrits were measured in normal male and female mice, as well as in females and castrated males after short-term (2 wk) and long-term (5-7 mo) testosterone intervention (50 mg/kg, weekly). Castrated males for long-term intervention were studied in parallel with the normal males to assess the effect of long-term testosterone deprivation. An additional short-term intervention study was conducted in females with a lower testosterone dose (5 mg/kg). Our results indicate no rheological difference among normal males, females, and castrated males at steady-state. Short-term high-dose testosterone increased hematocrit and whole-blood viscosity in both females and castrated males. This effect diminished after long-term treatment, in association with increased erythrocyte deformability in the testosterone-treated mice, suggesting the presence of adaptive mechanism. Considering that cardiovascular events in human trials are seen early after intervention, rheological changes as potential mediator of vascular events warrant further investigation.

High-Frequency Intra-operative Ultrasound-Guided Surgery of Superficial Intra-cerebral Lesions via a Single-Burr-Hole Approach

The study described here examined the feasibility of using high-frequency intra-operative ultrasound (hfioUS) guidance to resect superficial intra-cerebral lesions through a single burr hole. A cohort of 23 consecutive patients with a total of 24 intra-cerebral lesions (9 intra-cerebral metastases, 8 gliomas, 4 infections, 2 lymphomas and 1 cavernoma) were studied. All lesions could be localized and successfully resected, biopsied or aspirated, and histopathological diagnoses were obtained in all cases. The mean operating time was 59.6 ± 23.9 min. The mean cross-sectional lesion size was 6.4 ± 7.6 cm(2), and the mean cortex surface-to-lesion distance was 0.6 ± 0.8 cm. Our results illustrate the feasibility of identifying and resecting superficial intra-cerebral lesions under hfioUS guidance via a single-burr-hole approach. We were able to achieve short resection times with no post-operative complications in all patients, favorable conditions under which to start adjuvant therapy when indicated.

Combined administration of testosterone plus an ornithine decarboxylase inhibitor as a selective prostate-sparing anabolic therapy

Because of its anabolic effects on muscle, testosterone is being explored as a function‐promoting anabolic therapy for functional limitations associated with aging; however, concerns about testosterones adverse effects on prostate have inspired efforts to develop strategies that selectively increase muscle mass while sparing the prostate. Testosterones promyogenic effects are mediated through upregulation of follistatin. We show here that the administration of recombinant follistatin (rFst) increased muscle mass in mice, but had no effect on prostate mass. Consistent with the results of rFst administration, follistatin transgenic mice with constitutively elevated follistatin levels displayed greater muscle mass than controls, but had similar prostate weights. To elucidate signaling pathways regulated differentially by testosterone and rFst in prostate and muscle, we performed microarray analysis of mRNAs from prostate and levator ani of castrated male mice treated with vehicle, testosterone, or rFst. Testosterone and rFst shared the regulation of many transcripts in levator ani; however, in prostate, 593 transcripts in several growth‐promoting pathways were differentially expressed after testosterone treatment, while rFst showed a negligible effect with only 9 transcripts differentially expressed. Among pathways that were differentially responsive to testosterone in prostate, we identified ornithine decarboxylase (Odc1), an enzyme in polyamine biosynthesis, as a testosterone‐responsive gene that is unresponsive to rFst. Accordingly, we administered testosterone with and without α‐difluoromethylornithine (DFMO), an Odc1 inhibitor, to castrated mice. DFMO selectively blocked testosterones effects on prostate, but did not affect testosterones anabolic effects on muscle. Co‐administration of testosterone and Odc1 inhibitor presents a novel therapeutic strategy for prostate‐sparing anabolic therapy.

Topographic Classification of the Thalamus Surfaces Related to Microneurosurgery: A White Matter Fiber Microdissection Study

OBJECTIVE To describe the topographic anatomy of surgically accessible surfaces of the human thalamus as a guide to surgical exploration of this sensitive area. METHODS Using the operating microscope, we applied the fiber microdissection technique to study 10 brain specimens. Step-by-step dissections in superior-inferior, medial-lateral, and posterior-anterior directions were conducted to expose the surfaces and nuclei of the thalamus and to investigate the relevant anatomic relationships and visible connections. RESULTS There were 4 distinct free surfaces of the thalamus identified: lateral ventricle surface, velar surface, cisternal surface, and third ventricle surface. Each is described with reference to recognizable anatomic landmarks and to the underlying thalamic nuclei. The neural structures most commonly encountered during the surgical approach to each individual surface are highlighted and described. CONCLUSIONS Observations from this study supplement current knowledge, advancing the capabilities to define the exact topographic location of thalamic lesions. This improved understanding of anatomy is valuable when designing the most appropriate and least traumatic surgical approach to thalamic lesions. These proposed surface divisions, based on recognizable anatomic landmarks, can provide more reliable surgical orientation.

Lopinavir/Ritonavir Impairs Physical Strength in Association with Reduced Igf1 Expression in Skeletal Muscle of Older Mice

Background Late-middle age HIV patients are prone to fatigue despite effective viral control by antiretroviral therapies. Rodent models to recapitulate this phenotype are still not available. Hypothesis Drug treatment may compromise muscle strength and physical performance more in older individuals with pre-existing metabolic disorders than normal young ones. Methods Kaletra was given to overweight male mice at late-middle age and normal young adults; both on a rodent diet containing 30% fat calorie. Body composition and grip strength were measured at baseline and after drug treatment. Rota-rod running, insulin and glucose tolerance were measured at the end of the experiment. Drug effect on metabolic activity and spontaneous movements were assessed using the metabolic cage system. Representative muscle and fat tissue were analyzed for protein and mRNA expression. Selected findings were tested using murine C2C12 myotubes. Results Kaletra reduced grip strength in both young and older mice but impaired rotarod performance only in the old. Spontaneous movements were also reduced in Kaletra-treated old mice. Kaletra reduced IGF-1 expression in all muscle groups tested for the old and in cultured myotubes but to a less extent in the muscle of young animals. Reduced IGF-1 expression correlated with increased expression of muscle-specific atrogene MAFbx and MuRF1. Kaletra also increased abdominal fat mass markedly in the old animals and to a less extend in the young. Conclusion Long-term Kaletra intake aggravated abdominal obesity and impaired muscle strength. This effect was worse in older animals than in normal young adults.

Selection strategy for optimal keyhole approaches for MCA aneurysms: lateral supraorbital versus minipterional craniotomy

BACKGROUND/OBJECTIVE The lateral supraorbital (LS) and minipterional (MP) approaches have been reported for treating intracranial aneurysms as alternative to the pterional approach. We describe our decision making for selecting the minicraniotomy, LS versus MP, for managing noncomplex aneurysms of the middle cerebral artery (MCA), based on the depth of the aneurysm within the Sylvian fissure. METHODS We report on a consecutive case series of 50 patients who underwent clipping of 54 ruptured/unruptured MCA aneurysms by means of LS or MP craniotomies. The distance between the MCA (M1) origin and the aneurysmal neck is key to selection of the approach: LS was used for MCA aneurysms <15 mm from the M1 origin and MP for MCA aneurysms ≥15 mm from the M1 origin. RESULTS 11 of 50 patients presented with subarachnoid hemorrhage (10 ruptured MCA aneurysms). Overall, 59 aneurysms were successfully clipped (54 of the MCA). The mean distance between the M1 origin and the aneurysmal neck was 10.1 mm (range, 4-17 mm) for patients treated by LS and 20 mm (range, 15-30 mm) for those treated by MP. All but 1 MCA aneurysms were successfully treated. At last follow-up (mean, 14 months), no reperfusion of the clipped aneurysms was observed. CONCLUSION Our strategy for selecting the keyhole approach based on the depth of the aneurysm within the Sylvian fissure is efficient and safe. We suggest the use of the LS approach when the aneurysm is <15 mm from the M1 origin and the MP approach when the aneurysm is ≥15 mm from the M1 origin.