L-methylfolate augmentation of selective serotonin reuptake inhibitors (SSRIS) for major depressive disorder: Results of two randomized, double-blind trials

Introduction

Two randomized, controlled trials of L-methylfolate augmentation of SSRIs for major depressive disorder (MDD) were conducted using a novel study design (sequential parallel comparison design- SPCD).

Objectives/aims

To evaluate the efficacy of L-methylfolate augmentation using the Hamilton Depression Rating Scale.

Methods

In study one (TRD-1), 148 outpatients with SSRI-resistant MDD were enrolled in a 60-day, SPCD study, divided into two 30-day periods (phases 1 and 2). Patients were randomized 2:3:3 to receive L-methylfolate (7.5mg/d in phase 1, 15mg/d in phase 2), placebo in phase 1 followed by L-methylfolate 7.5mg/d in phase 2, or placebo for both phases. Study two (TRD-2) involved 75 patients and was identical in design to TRD-1 except for the dose of L-methylfolate (15mg only).

Results

In the TRD-1 Study, L-methylfolate 7.5 mg/d was not found to be more effective than placebo. In phase 1 of the TRD-2 Study, 37% of patients on L-methylfolate 15mg/d responded and 18% of placebo patients responded, while in phase 2 among placebo non-responders, the response rates were 28% on L-methylfolate 15mg/d and 9.5% on placebo. When phases 1 and 2 were pooled according to the SPCD model, the difference in response rates was statistically significant in favor of L-methylfolate (p = 0.0399). The rates of spontaneously reported AEs and rates of study discontinuation appear r comparable between L-methylfolate and placebo in both studies. Rates of study discontinuation were also comparable

Conclusions

These studies suggest that L-methylfolate 15 mg/d may be a safe and effective augmentation strategy for inadequate response to SSRIs.

A Phase 1B, randomized, double blind, placebo controlled, multiple-dose escalation study of NSI-189 phosphate, a neurogenic compound, in depressed patients

We wanted to examine tolerability and efficacy of NSI-189, a benzylpiperizine-aminiopyridine neurogenic compound for treating major depressive disorder (MDD). This was a Phase 1B, double blind, randomized, placebo controlled, multiple-dose study with three cohorts. The first cohort received 40 mg q.d. (n=6) or placebo (n=2), the second cohort 40 mg b.i.d. (n=6) or placebo (n=2), and the third cohort 40 mg t.i.d. (n=6) or placebo (n=2). Twenty-four patients with MDD were recruited, with the diagnosis and severity confirmed through remote interviews. Eligible patients received NSI-189 or placebo for 28 days in an inpatient setting with assessments for safety, pharmacokinetics (PK) and efficacy. Outpatient follow-up visits were conducted until day 84 (±3). NSI-189 was relatively well tolerated at all doses, with no serious adverse effects. NSI-189 area under the curve increased in a dose-related and nearly proportional manner across the three cohorts, with a half-life of 17.4-20.5 h. The exploratory efficacy measurements, including Symptoms Of Depression Questionnaire (SDQ), Montgomery-Asberg Depression Scale (MADRS), Clinical Global Impressions-Improvement (CGI-I), and The Massachusetts General Hospital (MGH) Cognitive and Physical Functioning Questionnaire (CPFQ) showed a promising reduction in depressive and cognitive symptoms across all measures for NSI-189, with significant improvement in the SDQ and CPFQ, and a medium to large effect size for all measures. These improvements persisted during the follow-up phase. In summary, NSI-189 shows potential as a treatment for MDD in an early phase study. The main limitation of this preliminary study was the small sample size of each cohort.

Is S-Adenosyl Methionine (SAMe) for Depression Only Effective in Males? A Re-Analysis of Data from a Randomized Clinical Trial

OBJECTIVE

The aim of this study was to examine whether gender differences may have affected treatment response to S-adenosyl methionine (SAMe) in a recent failed randomized clinical trial (RCT) for adults with major depressive disorder.

METHODS

Data from a 2-site, 12-week, double-blind RCT (n=189) assessing the efficacy of SAMe vs. placebo and a comparator selective serotonin reuptake inhibitor (escitalopram) were subjected to post-hoc analyses to evaluate effects of patient gender on treatment response.

RESULTS

When assessing the efficacy outcomes within each gender separately, SAMe was superior to placebo among males (n=51), but not among females (n=62). Males showed a significant reduction of depression severity from baseline to study endpoint on the 17-item Hamilton Depression Rating Scale (4.3 point difference; p=0.034; d=0.95), while females did not show significant change. This finding emerged despite equivalence on baseline measures of depression severity between the gender groups.

CONCLUSION

RESULTS of this secondary data analysis suggest that gender might impact the antidepressant efficacy of SAMe, with greater therapeutic effect found in males. The underlying mechanism is still relatively unknown. Further work is needed to replicate this observation in independent samples.Clinicaltrials.gov identifier: NCT00101452.

The potential relationship between levels of perceived stress and subtypes of major depressive disorder (MDD)

OBJECTIVE

We wanted to explore whether major depressive disorder (MDD) subtypes (melancholic depression, atypical depression, double depression, and MDD with anger attacks) were related to levels of perceived stress, as measured by the Perceived Stress Scale (PSS).

METHOD

Our sample [n = 298; female = 163 (55%); mean age 40.1 +/- 10.5 years] consisted of out-patients with MDD. The Structured Clinical Interview for DSM-III-R, the 17-item Hamilton Rating Scale for Depression, the Anger Attack Questionnaire, and the PSS were administered prior to initiating treatment.

RESULTS

Depressed women had significantly higher levels of perceived stress (P = 0.02) than depressed men. Greater severity of depression at baseline was significantly related to higher levels of perceived stress (P < 0.0001). After adjusting for age, gender, and severity of depression at baseline, higher levels of perceived stress were significantly related to the presence of anger attacks (P < 0.0001; t = -4.103) as well as to atypical depression (P = 0.0013; t = 3.26).

CONCLUSION

Out-patients with MDD who are more irritable and/or present with atypical features have higher levels of perceived stress, indicating a potential reactive component to their depression.

Clinical and sociodemographic predictors of response to augmentation, or dose increase among depressed outpatients resistant to fluoxetine 20 mg/day

OBJECTIVE

Patients with major depressive disorder often show only partial or no response to antidepressants, necessitating next-step interventions such as dose increase or augmentation. Factors moderating response to these next-step interventions are not well-studied.

METHOD

In this randomized, double-blind investigation of next-step treatments in 101 outpatients who failed to respond to fluoxetine 20 mg for 8 weeks, the impact of depressive course and sociodemographic factors on likelihood of treatment response following dose increase or lithium or desipramine augmentation was examined.

RESULTS

After controlling for depression severity at baseline, current marriage and earlier onset of depression were associated with greater likelihood of response in a logistic regression. Intervention strategy was not predictive of response.

CONCLUSION

Marital status and earlier onset of depression may be clinically useful in predicting outcome following any next-step intervention for treatment resistance, rather than with particular strategies.

Management of major depression in the primary care setting

BACKGROUND

Patients treated in community clinics, particularly those of minority status, may rely more heavily on primary care physicians (PCPs) for the diagnosis and management of depression. We wished to determine how PCPs in a community clinic setting initially manage patients newly diagnosed with major depression.

METHODS

698 patients were screened for major depression by the Structural Clinical Interview for DSM-III-R in a community-based primary care health center. Forty outpatients (29 Hispanic) were found to suffer from major depression. A letter explaining positive findings was sent to the patients' PCPs. Medical record charts were reviewed 3 months later to determine the PCP's management following the diagnosis.

RESULTS

Of the 38 patients who remained in the study at 3 months, 20 (53%) received no intervention from the PCP by the end of 3 months after diagnosis, and of these, 14 were Hispanic. Five (13%) were prescribed an antidepressant by the PCP. Nine (24%) were referred to mental health services for medication, psychotherapy or combination treatment. Four (11%) were prescribed an antidepressant and then referred to mental health services. Differences between management of Hispanic and non-Hispanic patients were not statistically significant.

CONCLUSIONS

Independent screening by psychiatrists in primary care settings may not be adequate enough to ensure appropriate management of depression by PCPs. Possible explanations may include time constraints during primary care visits, patient and/or physician reticence, and insufficient education of PCPs about depression.

Docosahexanoic acid and omega-3 fatty acids in depression

Geographic areas where consumption of DHA is high are associated with decreased rates of depression. DHA deficiency states, such as alcoholism and the postpartum period, also are linked with depression. Individuals with major depression have marked depletions in omega-3 FAs (especially DHA) in erythrocyte phospholipids compared with controls. These data suggest that DHA may be associated with depression, and the limited data available on supplementation with DHA or other omega-3 FAs seem to support the hypothesis that DHA may have psychotropic effects. Overall, the use of EFAs is promising, particularly in view of the many illnesses potentially treatable with these substances; however, larger, carefully designed studies are needed to establish whether DHA is an effective and safe antidepressant, mood stabilizer, or antipsychotic. A few preliminary trials of DHA are in progress, but no studies comparing DHA against placebo or against an established antidepressant have been carried out. Studies to address this issue are being developed at the Massachusetts General Hospital. Studies likely will require escalating doses of DHA, eventually reaching high levels so as to ensure that patients will avoid a potentially ineffective subclinical dose. Careful monitoring of dietary intake among subjects also will necessary because a high intake of omega-3-rich foods may confound results. Finally, large-scale, placebo-controlled, double-blind trials comparing the efficacy and safety of DHA against standard antidepressants are required before psychiatrists can recommend DHA therapy as effective and safe for the treatment of depression and other mood disorders. Given the popularity of self-medication by patients who already are taking marketed antidepressants, studies examining the use of DHA as an augmentor to standard antidepressants may answer whether DHA can occupy a niche as an augmenting agent for patients who have made a partial response or have not responded to conventional antidepressants. Considering that natural medications generally seem best for treating mild to moderate illness, the role of DHA as a therapy for minor and subsyndromal depression also should be considered. It is hoped that studies of these types will help to clarify some of the knowledge gaps outlined in this article.

Anemia and macrocytosis in the prediction of serum folate and vitamin B12 status, and treatment outcome in major depression

BACKGROUND

Folate and B12 deficiencies may result in macrocytic anemia, and are common in major depression; hypofolatemia may result in poorer antidepressant response. We wished to determine whether anemia or macrocytosis predict hypofolatemia, low B12, or refractoriness to antidepressants.

METHODS

After obtaining serum folate, B12, and hematological indices, 213 depressed adults were treated with fluoxetine 20 mg/day. Amelioration of depressive symptoms was measured.

RESULTS

Neither macrocytosis nor anemia predicted low serum folate/B12, or antidepressant refractoriness. Among 39 patients with hypofolatemia, none had macrocytosis; 28% had low HCT; 41% had low RBC. Among 25 patients with low B12, none had macrocytosis; 24% had low HCT; 28% had low RBC. Among non-responders, 3% had macrocytosis; 24% had low HCT; 25% had low RBC.

CONCLUSION

Anemia and macrocytosis should not be used to predict folate or B12 deficiencies, or refractoriness to antidepressants. Measurement of folate and B12 should be considered when evaluating treatment refractoriness.

Strategies for managing depression refractory to selective serotonin reuptake inhibitor treatment: a survey of clinicians

OBJECTIVE

To examine treatment practices in cases where selective serotonin reuptake inhibitors (SSRIs) are ineffective.

METHODS

We surveyed 801 clinicians (including 630 psychiatrists) attending the Massachusetts General Hospital's annual psychopharmacology review course. Clinicians were presented with a vignette about a patient with depression who had responded partially to an SSRI and were asked to choose among various strategies available to manage this patient.

RESULTS

Of those surveyed, 466 clinicians had been in practice a mean of 16.6 years (SD 10.7). Not all clinicians chose to answer every question. Among 455 respondents, 84% (n = 382) chose to increase the dose of the SSRI, 10% (n = 47) chose augmentation or combination, and 7% (n = 31) opted for switching agents. When asked to switch to another agent, 448 responded, of whom 52% (n = 235) chose a newer antidepressant, 34% (n = 152) chose another SSRI, 10% (n = 44) chose a tricyclic antidepressant (TCA), 2% (n = 8) chose a serotonin norepinephrine reuptake inhibitor (SNRI), 1% (n = 5) chose a monoamine oxidase inhibitor (MAOI), and 1% (n = 4) chose an undefined "other" agent. Among 445 respondents, bupropion was the most widely chosen augmenting agent (30%, n = 134), followed by lithium (22%, n = 98). West coast and Canadian clinicians preferred to switch to another SSRI rather than to a newer antidepressant. Canadian clinicians preferred lithium to bupropion as their first-choice augmenting agent, as did clinicians from academic settings. Clinicians from community, individual practice, or group settings favoured bupropion. More experienced clinicians preferred bupropion as a first-choice augmenter, whereas less experienced ones showed a slight preference for lithium. Canadian clinicians were more likely to use MAOIs as second-line agents.

CONCLUSIONS

Clinicians in this sample often followed strategies different from those recommended in the literature. Bupropion may have an important role in augmentating treatment with SSRIs.

The DNA binding activity of C/EBP transcription factor is regulated in the G1 phase of the hepatocyte cell cycle

We have isolated the promoter of the rat C/EBP alpha gene and find a high degree of homology with the mouse gene, particularly in putative regulatory domains. Transactivation of this promoter by ectopic expression of rat C/EBP beta occurs through a C/EBP regulatory domain at position -170 to -195. An oligonucleotide corresponding to this domain binds to complexes expressed in rat liver that comprise C/EBP alpha-C/EBP beta heterodimers (alpha beta) as well as C/EBP beta complexed with itself and/or other unidentified nuclear factors (beta 1, beta 2, and beta 3). The DNA binding activity of these complexes changes both qualitatively and quantitatively following partial hepatectomy. Within 2-5 h postsurgery, the binding activity of the alpha beta complexes drops severalfold, reaching a nadir by 20 h. During the ensuing 3-8 days, as regeneration nears completion, this activity slowly returns to normal quiescent liver levels. Western blot analysis shows 3 major C/EBP alpha polypeptide species (42, 40, and 30 kDa), whose abundance in general parallels the decrease and recovery in DNA binding activity. In contrast to C/EBP alpha behavior, the DNA binding activity of the beta complexes is transiently induced severalfold during the early G1 period between 2 and 6 h posthepatectomy. The major C/EBP beta polypeptide is the 32-kDa LAP protein, whereas the LIP protein (21 kDa) is weakly expressed. Both remain essentially constant throughout the course of regeneration, suggesting that changes in DNA binding activity may reflect changes in the complexed proteins rather than the C/EBP beta polypeptides themselves. In primary hepatocyte cultures, under growth supporting conditions, in the absence of growth factors proliferation is negligible; C/EBP alpha is abundantly expressed at the outset, but is then extensively down-regulated. Epidermal growth factor causes further decay of C/EBP alpha polypeptides and DNA binding activity, and down-regulates C/EBP beta DNA binding activity as well. Addition of transforming growth factor beta completely antagonizes the effects of epidermal growth factor on C/EBP beta activity, and partially overcomes the effect on C/EBP alpha. These results demonstrate that the DNA binding activity of C/EBP alpha and C/EBP beta complexes is regulated in the regenerating liver, and in hepatocyte cultures responding to growth factors that regulate their proliferation.

Cell-extracellular matrix interactions can regulate the switch between growth and differentiation in rat hepatocytes: reciprocal expression of C/EBP alpha and immediate-early growth response transcription factors

Previous investigations have shown that culture of freshly isolated hepatocytes under conventional conditions, i.e., on dried rat tail collagen in the presence of growth factors, facilitates cell growth but also causes an extensive down-regulation of most liver-specific functions. This dedifferentiation process can be prevented if the cells are cultured on a reconstituted basement membrane gel matrix derived from the Englebreth-Holm-Swarm mouse sarcoma tumor (EHS gel). To gain insight into the mechanisms regulating this response to extracellular matrix, we are analyzing the activities of two families of transcription factors, C/EBP and AP-1, which control the transcription of hepatic and growth-responsive genes, respectively. We demonstrate that isolation of hepatocytes from the normal quiescent rat liver by collagenase perfusion activates the immediate-early growth response program, as indicated by increased expression of c-jun, junB, c-fos, and c-myc mRNAs. Adhesion of these activated cells to dried rat tail collagen augments the elevated levels of these mRNAs for the initial 1 to 2 h postplating; junB and c-myc mRNA levels then drop steeply, with junB returning to normal quiescence and the c-myc level remaining slightly elevated during the 3-day culture period. Levels of c-jun mRNA and AP-1 DNA binding activity, however, remain elevated from the outset, while C/EBP alpha mRNA expression is down-regulated, resulting in a decrease in the steady-state levels of the 42- and 30-kDa C/EBP alpha polypeptides and C/EBP alpha DNA binding activity. In contrast, C/EBP beta mRNA production remains at near-normal hepatic levels for 5 to 8 days of culture, although its DNA binding activity decreases severalfold during this time. Adhesion of hepatocytes to the EHS gel for the same period of time dramatically alters this program: it arrests growth and inhibits AP-1 DNA binding activity and the expression of c-jun, junB, and c-myc mRNAs, but, in addition, it restores C/EBP alpha mRNA and protein as well as C/EBP alpha and C/EBP beta DNA binding activities to the abundant levels present in freshly isolated hepatocytes. These changes are not due merely to growth inhibition, because suppression of hepatocyte proliferation on collagen by epidermal growth factor starvation or addition of transforming growth factor beta does not inhibit AP-1 activity or restore C/EBP alpha DNA binding activity to normal hepatic levels. These data suggest that expression of the normal hepatic phenotype requires that hepatocytes exist in a G0 state of growth arrest, facilitated here by adhesion of cells to the EHS gel, in order to express high levels of hepatic transcription factors such as C/EBP alpha.

Differential regulation of glucose transporter 1 and 2 mRNA expression by epidermal growth factor and transforming growth factor-beta in rat hepatocytes

We have examined by Northern blot analysis the expression of two members of the glucose transporter family of genes (GLUT-1 and GLUT-2) in regenerating liver and in hepatocytes cultured under various conditions. GLUT-1, although thought to be a growth-associated gene, is not expressed in normal or regenerating liver, whereas GLUT-2, a liver-specific gene, is abundant in normal liver and gradually up-regulated during liver regeneration. Conversely, in hepatocytes cultured conventionally on dried rat tail collagen (RTC) in the presence of EGF and insulin, which potentiate proliferation, GLUT-1 mRNA is rapidly and abundantly expressed, whereas GLUT-2 is depressed. To investigate the causes of this "switch" in glucose transporter expression seen when hepatocytes are removed from the liver and cultured under the conventional proliferative conditions, we examined the effects of specific growth factors and extracellular matrices on cultured hepatocytes. EGF, a potent liver mitogen, although causing a threefold induction of GLUT-1, was found to have no effect on GLUT-2 expression, suggesting that the increase in GLUT-2 seen in regenerating liver is not due to EGF. Inhibition of protein synthesis by cycloheximide in cultured hepatocytes does not prevent the induction of GLUT-1 mRNA. In addition, treatment of cells with cycloheximide appears to stabilize the GLUT-2 mRNA, preventing the usual down-regulation of this gene in cultured hepatocytes. The expression of the two glucose transporter mRNAs also differed when the hepatocytes were adherent to particular cell matrices. Culture of hepatocytes on a reconstituted basement membrane gel matrix (EHS) is known to restrain their growth and mediate high levels of differentiated hepatocytic functions that are lost under conventional culture conditions. Unlike cells on RTC, hepatocytes on EHS expressed low levels of GLUT-1 mRNA, and decreased GLUT-2 mRNA. TGF-beta, an attenuator of DNA synthesis, when added to cultures on RTC, substantially down-regulated GLUT-2 but had no effect on GLUT-1. We propose that the effectors, EGF, TGF-beta and basement membrane components, play a significant role in the regulation of expression of GLUT-1 and GLUT-2 in hepatocytes.

Growth-dependent inhibition of CCAAT enhancer-binding protein (C/EBP alpha) gene expression during hepatocyte proliferation in the regenerating liver and in culture

As an approach to understanding physiological mechanisms that control the proliferation of highly differentiated cells, we are addressing whether certain hepatic transcription factors participate in mechanisms that control the growth of hepatocytes. We have focused on CCAAT enhancer-binding protein (C/EBP alpha), a transcription factor which is highly abundant in normal liver and is considered to regulate expression of many genes, including some involved in energy metabolism (S. L. McKnight, M. D. Lane, and S. Gluecksohn-Walsh. Genes Dev. 3:2021-2024, 1989). Using Northern (RNA) blot analysis, we have examined the expression of C/EBP alpha mRNA during liver regeneration and in primary cultures of hepatocytes. C/EBP alpha mRNA levels decrease 60 to 80% within 1 to 3 h after partial hepatectomy as the cells move from G0 to G1 and decrease further when cells progress into S phase. Run-on transcription analysis is in agreement with the Northern blot data, thus suggesting that C/EBP alpha is transcriptionally regulated in regenerating liver. C/EBP alpha mRNA expression also decreases dramatically during the growth of freshly isolated normal hepatocytes cultured under conventional conditions (on dried rat tail collagen; stimulated to proliferate by epidermal growth factor [EGF] and insulin). Cultures of hepatocytes on rat tail collagen in the presence or absence of EGF clearly show that within 3 h, EGF depresses C/EBP alpha mRNA expression and that this effect is substantially greater by 4 h. Inhibition of protein synthesis in the liver by cycloheximide or in cultured hepatocytes by puromycin or cycloheximide effectively blocks the down-regulation of C/EBP alpha gene expression, apparently by stabilizing the normal rapid turnover of the C/EBP alpha mRNA (half-life of <2 h). This drop in C/EBP alpha gene expression in response to activation of hepatocyte growth is consistent with the proposal that C/EBP alpha has an antiproliferative role to play in highly differentiated cells (R. M. Umek, A. D. Friedman, and S. L. McKnight, Science 251: 288-292, 1991).