Immunomodulating activities of cocaine — Evaluation of lymphocyte transformation related to other immune functions

Human papillomavirus awareness among HIV-infected drug users in two urban areas

Summary

Human papillomavirus (HPV) is the cause of cervical and anal cancer. Human immunodeficiency virus (HIV) infection and cocaine use are associated with increased risk for HPV infection and associated diseases, but little is known about HIV-infected drug users' awareness of HPV. We investigate HPV awareness among HIV-infected, sexually-active crack cocaine users from two inner-city hospitals in Florida and Georgia during their inpatient stays. Multivariate logistic regression analysis was used to examine potential correlates of HPV awareness. We interviewed 215 participants (110 women; 105 men) about their awareness of HPV infection. Overall, only 25% of respondents reported having heard of HPV. The odds of having heard of HPV were greater for respondents having a high-school degree or higher, having ever gone to an HIV provider for HIV care, and having two or more sexual partners. Despite increased susceptibility to HPV infection and HPV-related cancers, our study findings suggest that sexually-active HIV-infected crack cocaine users have little awareness of HPV and highlight the need for programmes targeting HPV education for HIV-infected crack cocaine drug users.

The manifestation of cocaine-induced midline destructive lesion in bone tissue and its identification in human skeletal remains

Cocaine-induced midline destructive lesion (CIMDL) is a condition that may arise in response to chronic insufflation ("snorting") of cocaine. It is clinically diagnosed when the nasal septum, lateral nasal walls, and/or hard palate show signs of destruction in association with cocaine use. Although its true incidence is unknown, CIMDL is not an uncommon clinical finding amongst intranasal cocaine abusers and is likely to be encountered by forensic anthropologists and medical examiners working worldwide. Given the preponderance of drug abusers amongst the subjects of forensic casework, the ability to diagnose CIMDL in dry bone may provide crucial insight into an investigation and even help confirm an individual identification. This paper aims to make practicing forensic anthropologists aware of CIMDL. Through the analysis of existing clinical literature, patient CT scans, and histology sections, it works toward the establishment of formal diagnostic criteria for identifying CIMDL in human skeletal remains. Lytic destruction regularly involves the vomer and frequently extends to the perpendicular plate of the ethmoid, the palatal process of the maxillae or the palatine bones, and the inferior nasal conchae. The middle nasal conchae, medial walls of the maxillary sinuses, ethmoid sinuses, and cribriform plate are often damaged. Destruction may also implicate the superior nasal conchae, the orbit, and the sphenoid. Bones affected by CIMDL may contain necrotic lesions or may be absent entirely. Lesions show minimal, if any, signs of repair. The author proposes that this lack of new bone formation may be mediated by potentially elevated leptin levels in cocaine abusers and CIMDL patients and may be the key to differentiating CIMDL from other lytic processes of the midface.

The relationship between cocaine use and human papillomavirus infections in HIV-seropositive and HIV-seronegative women

Objective. Animal data suggest that cocaine has an immunosuppressive effect, but no human studies have been conducted to assess the relation of cocaine use with human papillomavirus (HPV) infection, the viral cause of cervical cancer. Since both cocaine use and HPV infection are common among HIV-positive women, we sought to determine whether use of cocaine and/or crack influences the natural history of HPV among women with or at high risk of HIV. Methods. Women enrolled in the Women's Interagency HIV Study (2278 HIV-seropositive and 826 high-risk seronegative women) were examined every six months for up to 9.5 years with Pap smear, collection of cervicovaginal lavage (CVL) samples, and detailed questionnaires regarding health and behavior, including use of crack and cocaine (crack/cocaine). CVLs were tested for HPV DNA by PCR, with genotyping for over forty HPV types. Results. In multivariate logistic regression models, censoring women treated for cervical neoplasia, crack/cocaine use within the last six months was associated with prevalent detection of oncogenic HPV DNA (odds ratio [OR] = 1.30 (1.09–1.55)), and with oncogenic HPV-positive squamous intraepithelial lesions (SIL) (OR = 1.70 (1.27–2.27)), following adjustment for age, race, HIV-serostatus, and CD4+ T-cell count, the number of sexual partners in the past six months, and smoking. In multivariate Cox models crack/cocaine use was also associated with a trend that approached significance in regard to incident detection of oncogenic HPV-positive SIL (HR = 1.51, 95% CI 0.99–2.30), and while the rate of oncogenic HPV clearance was not related to cocaine use, the clearance of any SIL was significantly lower in those with versus those without recent crack/cocaine use (HR = 0.57, 95% CI 0.34–0.97). Conclusions. Cocaine use is associated with an increased risk of detection of both prevalent and incident oncogenic HPV infection, as well as an increased risk of HPV-positive SIL over time.

Drugs of abuse, immune modulation, and AIDS

Illicit drugs such as amphetamines, cocaine, marijuana, and opiates alter immune function and decrease host resistance to microbes in vitro and in experimental animal models. Effects on the immune system may be mediated indirectly as a result of drug interactions in the central nervous system (CNS) or directly through activation of cognate receptors on various immune cell types. For marijuana and opioids, seven-transmembranal G protein-coupled receptors have been identified in the CNS and in the immune system that may play a functionally relevant role in immune modulation. There is accumulating evidence that sigma(1) receptors play a comparable role in cocaine-mediated alteration of immune responses. A mode by which these exogenously introduced substances affects immunity and host resistance may be by perturbing the balance of Th(1) proinflammatory versus Th(2) anti-inflammatory cytokines and lipid bioeffectors. However, while illicit drugs have been documented to alter immune functions in vitro and in animal models, there is a paucity of controlled longitudinal epidemiological studies that definitively correlate immunosuppressive effects with increased incidence of infections or immune disorders in humans, including infection with the human immunodeficiency virus (HIV) or disease progression to AIDS.

The effect of cocaine sensitization on mouse immunoreactivity

Recent studies indicate a role of the immune system in the behavioral effects of cocaine in rodents. In the present study, we attempted to find a correlation between the behavioral changes induced by repeated, intermittent administration of cocaine and some immunological consequences of sensitization to cocaine. Male Albino Swiss mice were treated repeatedly (for 5 days) with cocaine (10 or 15 mg/kg, intraperitoneally, ip). On day 9, they received a challenge dose of cocaine (10 or 15 mg/kg). Acute administration of cocaine increased the locomotor activity of mice. In animals treated repeatedly with the higher dose of cocaine, the locomotor hyperactivity induced by a challenge dose of the psychostimulant (15 mg/kg) was ca. twice as high as that after its first administration; in consequence, evidence for behavioral sensitization was obtained. Immune functions were evaluated by measuring the ability of splenocytes to proliferate and to produce cytokines such as interferon-gamma (IFN-gamma), interleukin (IL)-4 and IL-10. Acute cocaine administration significantly decreased proliferation of splenocytes to concanavalin A (Con A) and increased their ability to produce IFN-gamma. Repeated intermittent treatment with cocaine in a dose of 10 mg/kg significantly decreased the thymus weight and the proliferative response of T cells to a suboptimal dose of Con A. Sensitization with the higher dose of cocaine significantly enhanced IFN-gamma production. These data indicate that cocaine sensitization results in the development of a tolerant state to the cocaine-induced suppression of a thymus dependent T-lymphocyte response. It may be suggested that the cocaine sensitization partly depends on the altered balance of cytokine production, e.g. an increase in IFN-gamma production. Since repeated, intermittent use of cocaine by humans leads to psychoses or craving for this drug, our findings also seem to indicate considerable importance of monitoring and correcting immune changes in the therapy of cocaine addiction.

Evidence of increased DNA content of murine thymocytes caused by cocaine

C57BL mice were injected intraperitoneally daily with 10 to 50 mg/kg of cocaine for five days. Four hours after the last injection, the thymuses were removed, and the effects on DNA and protein content of the surviving cells were measured. A dose-dependent increase in DNA content per cell, determined by UV spectrophotometric analysis, and a dose-dependent increase in protein content per cell, as measured using the Bio-Rad reagent, were observed. The increase in DNA content per cell was confirmed by H33258 staining of DNA as well as the diphenylamine assay. These changes were also observed when normal thymocytes were cultured with cocaine. Cell cycle analysis by flow cytometry of cocaine-treated cultures revealed the presence of aneuploid cells with increased DNA content. Fewer cells with aneuploidy were observed in experiments with significant apoptosis. Since both aneuploidy and enhanced apoptosis can be induced by cocaine and the amount of aneuploidy cells varies inversely with the degree of apoptosis, we hypothesize that cocaine causes DNA/chromosome damage, which eventually leads to cell death via the apoptosis pathway.

Midline Nasal and Hard Palate Destruction in Cocaine Abusers and Cocaine's Role in Rhinologic Practice

Intranasal cocaine abuse can lead to destruction of the palate and perforation of the nasal septum. The pathophysiology of cocaine-induced midline destructive lesions is multifactorial and includes local ischemia secondary to vasoconstriction, chemical irritation from adulterants put in “cut” cocaine, and infection secondary to trauma, impaired mucociliary transport, and decreased humoral and cell-mediated immunity. Cocaine abuse should be suspected in patients with a palatal or septal perforation of unknown etiology.

DNA toxicity of cocaine hydrochloride and cocaine freebase by means of DNA image analysis on Tetrahymena pyriformis

An assay for computerized scoring of the DNA content of the protozoan Tetrahymena pyriformis has been used for the detection of toxic responses to cocaine, since DNA is responsible for the replication of the genetic material and also reflects closely the number of chromosomes in the nucleus. Thus, doubling of the number of chromosomes in a cell will also correspond to doubling of the DNA content and of the nuclear volume. Two chemical forms of cocaine were used, cocaine hydrochloride and cocaine freebase (crack), at two doses of 1 and 2 mg per 100 ml of protozoan culture, respectively. Image analysis of the protozoan nucleus patterns revealed a rapid stimulating effect on the DNA content for both cocaine hydrochloride and freebase after 1 h of incubation. However, after 2 h of treatment a reduction, although not statistically significant, of the DNA content of the protozoan was observed. These observations were further correlated with the phagocytic activity of the protozoan cultures. This paper provides some possible explanations of the toxic effects of cocaine on this particular cell model.

Effect of short-term cocaine administration on the immune system of young and old C57BL/6 female mice

It has been shown that either cocaine or aging alone can alter the immune system. Our objective was to study if the immune system of aging mice was more susceptible to the effect of cocaine than the immune system of young mice. We used a short term (20 days) cocaine daily administration protocol. Cocaine only decreased the absolute number of Thy 1+, CD4+, CD8+, IL-2R+, Mac 1+ and B cells, in the spleen of old mice. Old untreated mice had a lower number of Thy 1+ cells in the thymus, and a higher number of cells expressing IL-2R. Cocaine decreased the number of Thy 1+ cells in the thymus of both age groups. Old mice showed a lower number of IgA+ plasma cells in the intestinal lamina propria (ILP) than young mice. Short term cocaine administration provoked a decrease in the number of CD4+ cells in young mice ILP and of CD8+ cells in old mice ILP. Our data suggest that cocaine can potentiate the effect of aging on the thymus and on the mucosal immune system. Taken together, our findings indicate that aging and cocaine can potentiate each other to impairing the host immune system.

Phagocytosis of the protozoon Tetrahymena pyriformis as an endpoint in the estimation of cocaine salt and cocaine freebase toxicity

Cells of the ciliated protozoon Tetrahymena pyriformis strain W, grown in a peptone-yeast medium, usually contain many phagocytic vacuoles. The phagocytic activity of this protozoon was studied in vivo using heat-inactivated yeast stained with carmine after exposing the cultures for 1 hour to different doses of cocaine hydrochloride or cocaine freebase (crack) (0.5, 1 or 2 mg/100 ml of protozoan culture).The number of vacuoles formed indicated the phagocytic activity. Cocaine hydrochloride and crack caused a decrease of the phagocytic activity of the protozoon (p < 0.05) when compared to the control cultures. Furthermore, the two chemical forms of cocaine, salt and free-base respectively, caused quantitatively different effects on the phagocytic activity. Crack produced an extensive decrease in phagocytosis, compared to equal concentrations of cocaine hydrochloride. These results suggest a possible relationship between cocaine abuse and the suppression of phagocytosis that may contribute to the impairment of immunity in drug misusers.

Suppression of splenic T lymphocyte proliferation by acute cocaine administration

We have recently demonstrated that cocaine administration has a limited effect on mitogen-stimulated T lymphocyte proliferation. The present study investigated the effect of cocaine on splenic T cell response to alloantigens. Rats received intraperitoneal injections of cocaine HCI, and splenocytes were isolated either thirty minutes or three hours post-administration. In the thirty minute exposure group, cocaine at 10.0 and 25.0 mg/Kg/B.Wt. suppressed (p<0.05) T cell proliferation in mixed lymphocyte cultures. Compared to control data, proliferation was decreased by 46.6% and 56.4%, respectively. However, this effect was not as pronounced in cells isolated three hours post-administration, indicating a transient inhibition of T cell function by cocaine. The decrease in splenic T cell proliferation in response to alloantigens in the thirty minute exposure group did not reflect alterations in calcium influx or IL-2 production. Although this study did not ascertain the exact mechanism of inhibition, these results demonstrate that short-term cocaine exposure can alter T cell reactivity to alloantigens, suggesting a reduction in the functional status of these cells.