Giuseppe Famularo

Acetyl-carnitine deficiency in Aids patients with neurotoxicity on treatment with antiretroviral nucleoside analogues

Objective:A severe dose-limiting axonal peripheral neuropathy may develop in subjects on treatment with the nucleoside analogues didanosine (ddI), zalcitabine (ddC), and stavudine (d4T). The impairment of mitrochondrial DNA synthesis is crucial to the pathogenesis of this disorder although other mechanisms have not been ruled out. The depletion of acetyl-carnitine, which regulates the metabolism and function of peripheral nerves, could contribute to the neurotoxicity of these compounds. Design:Non-randomized, cross-sectional study of selected patients. Methods:We measured the serum levels of acetyl- and total carnitine in 12 subjects with axonal peripheral neuropathy developed on treatment with different regimens of neurotoxic nucleoside analogues (ddI, ddC, d4T). Subjects who did not develop peripheral neuropathy while staying on treatment with ddI (n = 10) or zidovudine (n = 11) served as the control groups. HIV-negative subjects with axonal or demyelinating autoimmune neuropathies (n = 10) and healthy individuals (n = 13) were additional control groups. Results:Subjects experiencing axonal peripheral neuropathy on treatment with ddI, ddC and d4T had significantly reduced levels of acetyl-carnitine in comparison to the control groups. No difference was observed in the levels of total carnitine between study subjects and the control groups. Conclusions:Our results demonstrate that subjects who developed peripheral neuropathy while staying on treatment with ddI, ddC and d4T had acetyl-carnitine deficiency. The normal levels of total carnitine in the study group appear to indicate the specificity of the defect and rule out coexisting relevant nutritional problems. The critical role of acetyl-carnitine for the metabolism and function of the peripheral nerves supports the view that the acetyl-carnitine deficiency found in these subjects may contribute to the neurotoxicity of ddI, ddC and d4T, even though the interference with mitochondrial DNA synthesis is regarded as the main cause of their toxicity.

Prevention of radiation-induced diarrhea with the use of VSL#3, a new high-potency probiotic preparation

ditis. The time that elapsed between the upper endoscopy and the onset of fever (about 1 month) is also compatible with a typical incubation of a subacute endocarditis. Guidelines for prophylaxis in infectious endocarditis recommend antibiotic treatment before endoscopic procedures associated with high rates of bacteremia (esophageal dilation, variceal sclerotherapy, and laser therapy) in all patients, but also before therapeutic ERCP and percutaneous endoscopic gastrostomy in patients with lesions susceptible to endocarditis (heart valve diseases) (5). On the other hand, some studies have demonstrated that antibiotic prophylaxis can reduce the incidence of bacteremia, but it does not seem to prevent infectious postendoscopic endocarditis (6). We would recommend prophylactic therapy in all immune deficient patients with susceptible conditions even if they undergo low-risk endoscopic procedures. We hope that this prophylactic management can prevent infectious endocarditis, which is a potentially life-threatening disease.

High Dose L-Carnitine Improves Immunologic and Metabolic Parameters in Aids Patients

Several reports indicate that systemic carnitine deficiency could occur in acquired immunodeficiency disease syndrome (AIDS), and that primary and secondary carnitine deficiency leads to critical metabolic dysfunctions. L-carnitine supplementation to peripheral blood mononuclear cells (PBMCs) of AIDS patients resulted in significant enhancement of the phytohemagglutinin (PHA)-driven proliferative response. High dose L-carnitine administration (6 gr per day for two weeks) to AIDS patients treated with zidovudine also led to increased PBMCs proliferation and reduced blood levels of triglycerides. In addition, a reduction of beta 2-microglobulin serum levels as well as circulating tumor necrosis factor (TNF)-alpha, mostly in patients exhibiting highly elevated levels, were found at the end of the treatment period. Our data suggest that in vivo L-carnitine could prove useful in ameliorating both the immune response and lipid metabolism in patients with AIDS, irrespective of initial serum carnitines levels. The mechanism(s) accounting for the observed results are currently not clear. Further studies are needed to confirm the hypothesis that L-carnitine affects the expression of HIV-induced cytokine.

Soluble interleukin-2 receptor, interleukin-2 and interleukin-4 in sera and supernatants from patients with progressive systemic sclerosis.

We studied the sera of patients with progressive systemic sclerosis (PSS) for elevated levels of soluble interleukin‐2 receptor (sIL‐2R), interleukin‐2 (IL‐2) and interleukin‐4 (IL‐4). We also measured IL‐2, IL‐4 and B cell growth factor (BCGF) activity in supernatants of peripheral blood mononuclear cells from the same patients. The finding of elevated serum sIL‐2R and IL‐2, and the increased levels of IL‐2, IL‐4 and BCGF activity in culture supernatants indicates that T lymphocyte hyperactivity likely play a major role in PSS. The failure to detect under our experimental conditions a direct proliferative effect of recombinant IL‐2 on enriched normal B cells might suggest that IL‐4 is the cytokine mainly responsible of the BCGF activity recovered in PSS supernatants.

Heat shock proteins and their role in heart injury.

Heat shock protein (HSP) synthesis arises transiently as a tool to protect cellular homeostasis after exposure to heat and a wide spectrum of stressful and potentially deleterious stimuli. HSPs are “molecular chaperones” that recognize and form a complex with incorrectly folded or denatured proteins, which ultimately leads to correct folding, compartmentalization, or degradation. Accumulating evidence has implicated HSPs as mediators of myocardial protection, particularly in experimental models of ischemia and reperfusion injury. Impaired myocardial performance, which results from many factors, including hypoxia, is one of the main mechanisms responsible for heart failure in the critically ill patient. In this setting, different protective functions have been attributed to HSPs, which include repairing ion channels, restoring redox balance, interacting with nitric oxide–induced protection, inhibiting proinflammatory cytokines, and preventing apoptosis pathway activation. On this basis, novel therapeutic strategies by means of promising pharmacologic interventions and/or gene transfection techniques are being investigated for their potential to enhance HSP expression by myocardial cells, with the goal of improving the outcome of the critically ill patient.

Use of VSL#3 in the Treatment of Rotavirus Diarrhea in Children : Preliminary Results

We conducted a double-blind randomized placebo-controlled study to evaluate efficacy and tolerability of VSL♯3 (CD Pharma India) in the treatment of acute rotavirus diarrhea in children. The patients were randomly assigned to receive 4 days of oral treatment with VSL♯3 probiotic mixture or placebo in addition to usual care for diarrhea. Results: Out of 230 rotavirus-positive acute diarrhea children, 224 children completed the study, (113 in the drug group and 111 in the placebo group). At recruitment on Day 1, there were no significant differences between the 2 groups in terms of frequency of vomiting, mean loose stool frequency, stool consistency, and mean frequency of oral rehydration salts (ORS) and intravenous fluids administered. On Day 2, a lower mean stool frequency and improved stool consistency was noted in the drug group, which achieved statistical significance. This was also reflected in the lower volume of ORS administration in the drug group. Even on Day 3, mean loose stool frequency and frequency of ORS use and frequency of intravenous fluid use was significantly lower in the drug group. The differences in the frequency of loose stools persisted till 8 hours of Day 4. After this, as the placebo group also showed spontaneous improvement the difference between the 2 groups in terms of the overall stools frequency became comparable. However, the overall ORS requirement continued to be significantly lower in the drug group even on Day 4. The overall recovery rates were significantly better in the drug group compared with placebo. No side effects were noted with the use of the probiotic mixture. Use of probiotic mixture VSL♯3 in acute rotavirus diarrhea resulted in earlier recovery and reduced frequency of ORS administration reflecting decreased stool volume losses during diarrhea.

Carnitines and its congeners: a metabolic pathway to the regulation of immune response and inflammation.

Abstract: Carnitine and its congeners may regulate the immune networks, and their influence on functions of immune cells predominantly or exclusively relies on carnitine‐dependent energy production from fatty acids. A reduced pool of carnitines has been demonstrated in either serum or tissues, or both, from patients with a wide spectrum of disorders characterized by unregulated or impaired immune responses ranging from sepsis syndrome to systemic sclerosis, infection with human immunodeficiency virus, and chronic fatigue syndrome. Furthermore, experimental studies have consistently reported that the deranged immune responses and the less efficient inflammation towards infectious organisms associated with aging may be enhanced or modulated by treatment with carnitines. There is also evidence that carnitine deprivation could adversely affect the course of the sepsis syndrome, at least in experimental models, and preliminary studies suggest that carnitine deficiency is ultimately implicated in the pathophysiology of endotoxin‐mediated multiple organ failure. Several data indicate that carnitine deficiency is a contributing factor to the progression of infection with human immunodeficiency virus, and carnitine therapy in those patients could counteract the unregulated process of lymphocyte apoptosis and improve CD4 counts. Some case reports have suggested the use of carnitine for the treatment of the severe lactic acidosis that complicates in some patients the use of reverse transcriptase inhibitors.

L-Carnitine Reduces Lymphocyte Apoptosis and Oxidant Stress in HIV-1-Infected Subjects Treated with Zidovudine and Didanosine

Apoptosis is critical to the progression of human immunodeficiency virus-1 (HIV-1) infection. It appears reasonable that antiretroviral therapies may not achieve a full control of the infection in the absence of an impact on apoptosis. We assigned 20 asymptomatic HIV-infected subjects with advanced immunodeficiency to receive either zidovudine (AZT), and didanosine (DDI) or the same regimen plus L-carnitine, a known antiapoptotic drug, for 7 months. Immunologic and virologic parameters were measured at baseline and after 15, 60, 120, and 210 days of treatment. We assessed on each time point the following: (a) the frequency of peripheral blood apoptotic CD4 and CD8 lymphocytes, CD4 and CD8 cells with disrupted mitochondrial membrane potential, and CD4 and CD8 cells undergoing oxidant stress; (b) the expression of the molecular markers of apoptosis Fas and caspase-1; and (c) the expression of p35/cdk-5 regulatory subunit that is involved in regulating cell survival and apoptosis. Absolute CD4 and CD8 counts and plasma viremia were also measured. Apoptotic CD4 and CD8 cells, lymphocytes with disrupted mitochondrial membrane potential, and lymphocytes undergoing oxidant stress were greatly reduced in subjects treated with AZT and DDI plus L-carnitine compared with those who did not receive L-carnitine. Fas and caspase-1 were down-expressed and p35 over-expressed in lymphocytes from patients of the L-carnitine group. No difference was found in CD4 and CD8 counts and viremia between the groups. No toxicity of L-carnitine was recognized. The addition of L-carnitine is safe and allows apoptosis and oxidant stress to be greatly reduced in lymphocytes from subjects treated with AZT and DDI.

Stimulation of Immunity by Probiotics

The habit of consuming fermented milk has a long history going back hundreds of years. However, it was not until the end of the last century that the consumption of fermented milk was related to health.

Apoptosis and apoptosis-associated perturbations of peripheral blood lymphocytes during HIV infection: comparison between AIDS patients and asymptomatic long-term non-progressors

This study was designed to compare the degree of lymphocyte apoptosis and Fas–Fas ligand (FasL) expression in AIDS patients and long‐term non‐progressors (LTNPs) and correlate these parameters with apoptosis‐associated perturbations in lymphocyte function. LTNPs had a lower frequency of apoptotic CD4+ and CD8+ T cells compared with subjects with AIDS. This correlated with a lower frequency of cells expressing Fas and FasL. The frequency of selected lymphocyte populations exhibiting a disrupted mitochondrial transmembrane potential (ΔΨm) and increased superoxide generation was lower in LTNPs than in patients with AIDS; these abnormalities were associated with lower levels of caspase‐1 activation in LTNPs. The results indicate a significantly reduced level of apoptosis and apoptosis‐associated parameters in LTNPs than in patients developing AIDS. Based on these findings, a crucial role for mitochondria can be predicted in the process of lymphocyte apoptosis during the evolution of AIDS.