Alpha2 macroglobulin elevation without an acute phase response in depressed adults with Down's syndrome: implications

Acute phase protein and cytokine levels in serum and saliva: a comparison of detectable levels and correlations in a depressed and healthy adolescent sample

Recent research has examined associations between inflammation and mental health, and has increasingly focused on utilising younger samples to characterise the temporal relationship between inflammatory responses and the emergence of other symptoms. These studies have typically used blood to measure inflammation, although rates of detection for many inflammatory markers appear to be low. Saliva is a safe and low-cost alternative, and adult research has shown that levels of some salivary markers correlate well with those in serum. However, no research has examined this association in young people. This study examined 16 inflammatory markers in serum and saliva in 17 depressed adolescents and 18 healthy controls, aged 13-18 years. In general, detection rates were higher in saliva compared to in serum. When non-detectable levels were excluded, serum levels of C-reactive protein (CRP) correlated with salivary CRP (r=0.424, p=0.015), and this correlation appeared to only exist for those individuals with high levels of serum CRP (r=0.599, p=0.014). However, when non-detectable levels were included as zero, salivary levels of CRP, interleukin (IL)-2, IL-12p70, and interferon (IFN)-γ correlated with their serum counterparts. No significant clinical group differences in any acute phase proteins or cytokines were present. This study suggests that saliva can be used to measure inflammation in studies with adolescent participants, especially CRP, as it appears to correlate with systemic inflammation for those individuals who are expected to have high levels of inflammation. Implications for future directions in research on salivary inflammatory markers are discussed.

Depression in Down syndrome: a review of the literature

BACKGROUND

Depression has been frequently reported in individuals with Down Syndrome (DS). The aim of this article is to provide a comprehensive, critical review of the clinically relevant literature concerning depression in DS, with a focus on epidemiology, potential risk factors, diagnosis, course characteristics and treatment.

METHODS

We searched the PUBMED database (January 2011) using the keywords ("Depressive Disorder [MESH]" OR "Depression [MESH]" OR "depress* [All Fields]") AND ("Down Syndrome [MESH]" OR "Down syndrome [All Fields]" OR "Down's syndrome [All Fields]"). Review articles not adding new information, single case reports and papers focusing on subjects other than depression in DS were excluded.

RESULTS

The PUBMED search resulted in 390 articles, of which 30 articles were finally included. Recent information does not support earlier suggestions of an increased prevalence of depression in DS compared to other causes of Intellectual Disability (ID). However, individuals with DS show many vulnerabilities and are exposed to high levels of stressors that could confer an increased risk for the development of depression. Apart from general risk factors, several potential risk factors are more specific for DS, including smaller hippocampal volumes, certain changes in neurotransmitter systems, deficits in language and working memory, attachment behaviours and frequently occurring somatic disorders. Protective factors might play a role in reducing the vulnerability to depression. The diagnosis of depression in DS is mainly based upon observable characteristics, and therefore, the use of modified diagnostic criteria is advised. Although several common treatments, including antidepressants, electroconvulsive therapy and psychotherapy seem effective, there is evidence of undertreatment of depression in DS.

CONCLUSIONS

There are important limitations to our current clinical knowledge of depression in DS. Future studies should include systematic evaluations of pharmacotherapeutic and psychotherapeutic interventions.

Novel biomarkers predict liver fibrosis in hepatitis C patients: alpha 2 macroglobulin, vitamin D binding protein and apolipoprotein AI

BACKGROUND

The gold standard of assessing liver fibrosis is liver biopsy, which is invasive and not without risk. Therefore, searching for noninvasive serologic biomarkers for liver fibrosis is an importantly clinical issue.

METHODS

A total of 16 healthy volunteers and 45 patients with chronic hepatitis C virus (HCV) were enrolled (F0: n = 16, F1: n = 7, F2: n = 17, F3: n = 8 and F4: n = 13, according to the METAVIR classification). Three serum samples of each fibrotic stage were analyzed by two-dimension difference gel electrophoresis (2D-DIGE). The differential proteins were identified by the cooperation of MALDI-TOF/TOF and MASCOT; then western blotting and Bio-Plex Suspension Array were used to quantify the protein levels.

RESULTS

Three prominent candidate biomarkers were identified: alpha 2 macroglobulin (A2M) is up regulated; vitamin D binding protein (VDBP) and apolipoprotein AI (ApoAI) are down regulated. The serum concentration of A2M was significantly different among normal, mild (F1/F2) and advanced fibrosis (F3/F4) (p < 0.01). The protein levels of VDBP and ApoAI were significantly higher in normal/mild fibrosis, when compared to those in advanced fibrosis (both p < 0.01).

CONCLUSIONS

This study not only reveals three putative biomarkers of liver fibrosis (A2M, VDBP and ApoAI) but also proves the differential expressions of those markers in different stages of fibrosis. We expect that combination of these novel biomarkers could be applied clinically to predict the stage of liver fibrosis without the need of liver biopsy.

Metabolic depression in hibernation and major depression: an explanatory theory and an animal model of depression

Metabolic depression, an adaptive biological process for energy preservation, is responsible for torpor, hibernation and estivation. We propose that a form of metabolic depression, and not mitochondrial dysfunction, is the process underlying the observed hypometabolism, state-dependent neurobiological changes and vegetative symptoms of major depression in humans. The process of metabolic depression is reactivated via differential gene expression in response to perceived adverse stimuli in predisposed persons. Behavior inhibition by temperament, anxiety disorders, genetic vulnerabilities, and early traumatic experiences predispose persons to depression. The proposed theory is supported by similarities in the presentation and neurobiology of hibernation in bears and major depression and explains the yet unexplained neurobiological changes of depression. Although, gene expression is suppressed in other hibernators by deep hypothermia, bears were chosen because they hibernate with mild hypothermia. Pre-hibernation in bears and major depression with atypical features are both characterized by fat storage through overeating, oversleeping, and decreased mobility. Hibernation in bears and major depression with melancholic features are characterized by withdrawal from the environment, lack of energy, loss of weight from not eating and burning stored fat, changes in sleep pattern, and the following similar neurobiological findings: reversible subclinical hypothyroidism; increased concentration of serum cortisol; acute phase protein response; low respiratory quotient; oxidative stress response; decreased neurotransmitter levels; and changes in cyclic-adenosine monophosphate-binding activity. Signaling systems associated with protein phosphorylation, transcription factors, and gene expression are responsible for the metabolic depression process during pre-hibernation and hibernation. Antidepressants and mood stabilizers interfere with the hibernation process and produce their therapeutic effects by normalizing the fluctuation of activities in the different signaling systems, which are down-regulated during hibernation and depression and up-regulated during exodus from hibernation and the hypomanic or manic phase of mood disorders. The ways individuals cognitively perceive, understand, communicate, and react to the vegetative symptoms of depression, from downregulation in energy production, and in the absence of known medical causes, produce the other characteristics of depression including guilt, helplessness, hopelessness, suicidal phenomena, agitation, panic attacks, psychotic symptoms, and sudden switch to hypomanic or manic episodes. The presence of one or more of these characteristics depends on the person's neuropsychological function, its social status between the others, and the other's response to the person. Neurobiological changes associated with metabolic depression during entrance, maintenance, and exodus from hibernation in bears is suggested as a natural animal model of human depression and mood disorders.

Reference distributions for alpha2-macroglobulin: a practical, simple and clinically relevant approach in a large cohort

In this 11th article in a series, reference values of serum levels alpha(2)-macroglobulin alpha(2)M) are examined. The study is based on a cohort of 40,420 Caucasian individuals from northern New England that were tested in our laboratory between 1994 and 2000. Measurements were standardized against Certified Reference Material (CRM 470)/Reference Preparation for Proteins in Human Serum (RPPHS) and the results analyzed using a previously described statistical approach. Individuals with unequivocal laboratory evidence of inflammation (C-reactive protein >10 mg/L) were excluded in one leg of the study and included in the other, confirming that alpha(2)M does not respond to acute phase drive in man. Nephrotic syndrome, diabetes mellitus, and chronic liver disease have significant effect on levels of alpha(2)M. Dramatic changes occur during life with males higher from birth to age 12, females thereafter have higher values until the ninth decade. When values were expressed as multiples of the age- and gender-specific median levels, the resulting distributions fitted a log-Gaussian distribution well over a broad range. When patient data are normalized in this manner, the distribution parameters can be used to assign a centile corresponding to an individual's measurement thus simplifying interpretation.

Elevated levels of serum alpha2 macroglobulin in wild black bears during hibernation

Bear serum alpha(2) macroglobulin (alpha(2)M) was purified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and partially characterized by tryptic digestion of alpha(2)M and analysis of the peptides by peptide mass fingerprinting. The molecular weight of bear serum alpha(2)M was 181 kDa, same as for human serum alpha(2)M, on SDS-PAGE. However, the MALDI mass spectrum of the tryptic digested bear serum alpha(2)M showed that it is different from human alpha(2)M or other data bank proteins. Liquid chromatography (LC)/mass spectrometry (MS)/MS of the proteolytic products of bear serum alpha(2)M showed eight peptides that had similarities to human alpha(2)M suggesting that the protein of interest was indeed alpha(2)M of bear. The polyclonal antibody against bear serum alpha(2)M recognized only one protein from the western blot of bear serum proteins. It also recognized human alpha(2)M. The levels of serum alpha(2)M were significantly increased during hibernating state as compared to active state of bears indicating its protective role from the consequences of the metabolic depression during hibernation.

Circulating alpha-2-macroglobulin levels and depression scores in patients who underwent abdominal cancer surgery

BACKGROUND

Although depression is a predominant health care problem, it is difficult to diagnose in patients who underwent abdominal cancer surgery. Relevance of elevated levels of serum of alpha-2-macroglobulin (A2M) to psychological depression has been recently suggested.

PATIENTS AND METHODS

Serum A2M levels were measured and depression scores were determined by the Hospital Anxiety and Depression Scale before and 1 year after abdominal cancer surgery in 45 patients.

RESULTS

Serum levels of A2M and depression scores were significantly (P = 0.0006, P = 0.0045, respectively) increased after total gastrectomy compared with preoperative values, whereas there was no interval change in both measurements of patients having colorectal resection. Of the patients who had undergone distal or total gastrectomy for gastric cancer, serum A2M concentrations in a depressed group were significantly higher (P = 0.028) than those in non-depressed group.

CONCLUSIONS

Patients with total gastrectomy are predisposed to depression, and circulating A2M elevation may be implicated in the development of postoperative depression in these patients.

Challenging behaviours should not be considered as depressive equivalents in individuals with intellectual disability

BACKGROUND

Depression is one of the most common forms of psychopathology in people with intellectual disability (ID). The present study evaluated the utility of an expanded assessment of psychiatric symptoms and challenging behaviours, as measured by the Clinical Behavior Checklist for Persons with Intellectual Disabilities (CBCPID).

METHODS

The CBCPID was administered to 92 people with ID, 35 of whom were diagnosed with a depressive disorder.

RESULTS

Item and factor analysis of the scale indicated that depression was best assessed using the core DSM-IV symptoms of depressive disorder. Challenging behaviours such as self-injury or aggression were not closely associated with depression. Short scales using the core DSM-IV symptoms of depression were highly internally consistent. There was also evidence of the validity of these scales.

CONCLUSIONS

This study found no evidence that challenging behaviours were depressive equivalents in this population. The present authors conclude that the assessment of depression in people with ID should focus on the core DSM-IV symptoms of depression.

Changes during hibernation in different phospholipid and free and esterified cholesterol serum levels in black bears

During hibernation, fat is known to be the preferred source of energy. A detailed analysis of different phospholipids, as well as free and esterified cholesterol, was conducted to investigate lipid abnormalities during hibernation. The levels of total phospholipids and total cholesterol in the serum of black bears were found to increase significantly in hibernation as compared with the active state. Both free and esterified cholesterol were increased in the hibernating state in comparison with the active state (P < 0.05). The percentage increase during hibernation was more in free cholesterol (57%) than in esterified cholesterol (27%). Analysis of subclasses of serum phospholipids showed that choline containing phospholipids, i.e., sphingomyelin (SPG) (14%) and phosphatidylcholine (PC) (76%), are the major phospholipids in the serum of bear. The minor phospholipids included 8% of phosphatidylserine (PS) + phosphatidylinositol (PI), while phosphatidylethanolamine (PE) was only 2% of the total phospholipids. A comparison of phospholipid subclasses showed that PC, PS + PI and SPG were significantly increased, while PE was significantly decreased (P < 0.05) in the hibernating state as compared with the active state in black bears. These results suggest that the catabolism of phospholipids and cholesterol is decreased during hibernation in black bears, leading to their increased levels in the hibernating state as compared with the active state. In summary, our results indicate that serum cholesterol and phospholipid fractions (except PE) are increased during hibernation in bears. It is proposed that the increase of these lipids may be due to the altered metabolism of lipoproteins that are responsible for the clearance of the lipids.

Increased oxidative stress and decreased activities of Ca(2+)/Mg(2+)-ATPase and Na(+)/K(+)-ATPase in the red blood cells of the hibernating black bear

During hibernation, animals undergo metabolic changes that result in reduced utilization of glucose and oxygen. Fat is known to be the preferential source of energy for hibernating animals. Malonyldialdehyde (MDA) is an end product of fatty acid oxidation, and is generally used as an index of lipid peroxidation. We report here that peroxidation of lipids is increased in the plasma and in the membranes of red blood cells in black bears during hibernation. The plasma MDA content was about four fold higher during hibernation as compared to that during the active, non-hibernating state (P < 0.0001). Similarly, MDA content of erythrocyte membranes was significantly increased during hibernation (P < 0.025). The activity of Ca(2+)/Mg(2+)-ATPase in the erythrocyte membrane was significantly decreased in the hibernating state as compared to the active state. Na(+)/K(+)-ATPase activity was also decreased, though not significant, during hibernation. These results suggest that during hibernation, the bears are under increased oxidative stress, and have reduced activities of membrane-bound enzymes such as Ca(2+)/Mg(2+)-ATPase and Na(+)/K(+)-ATPase. These changes can be considered part of the adaptive for survival process of metabolic depression.