Sudomotor function and sweat gland innervation in galanin knockout mice

The presence of galanin and galanin binding sites in sweat gland has been demonstrated previously. In order to investigate whether galanin can influence sweat gland function, we compared sweating induced in footpads of wild type and galanin knockout mice by cholinergic and thermal stimulation using the silicone impression technique. Pilocarpine injections resulted in a similar number of reactive sweat glands and non-significant difference in the amount of sweat secretion in wild type and galanin knockout mice. However, thermal stimulation led to a significant increase in the number of secreting sweat glands in galanin knockout mice. To further evaluate possible differences in the innervation of sweat glands that could explain differences in their secretory activity, immunohistochemical labeling of cutaneous and sudomotor innervations against protein gene product 9.5, vasoactive intestinal polypeptide and choline acetyltransferase in plantar pads was performed. Immunohistochemical analysis revealed no significant differences in the distribution and intensity of the innervations between wild type mice and galanin knockout mice. Although our results indicate normal cholinergic responses and innervation of the sweat glands in galanin knockout mice, they also demonstrate that galanin plays a role in regulating the sudomotor activity in response to thermal stimulation.

Effect of escitalopram on hot flash interference: a randomized, controlled trial

OBJECTIVE

To estimate the effect of escitalopram (10-20 mg/d) versus placebo for reducing hot flash interference in daily life and understand correlates and predictors of reductions in hot flash interference, a key measure of quality of life.

DESIGN

Multisite, randomized, double-blind, placebo-controlled clinical trial.

SETTING

MsFLASH clinical sites in Boston, Indianapolis, Oakland, and Philadelphia.

PATIENT(S)

A total of 205 midlife women (46% African-American) who met criteria participated.

INTERVENTION(S)

After baseline, women were randomized to one pill of escitalopram 10 mg/d (n = 104) or placebo (n = 101) with follow-up at 4 and 8 weeks. At week 4, those not achieving 50% fewer hot flashes were increased to two pills daily (20 mg/d or 2 placebo pills).

MAIN OUTCOME MEASURE(S)

The Hot Flash Related Daily Interference Scale; correlates were variables from hot flash diaries; predictors were baseline demographics, clinical variables, depression, anxiety, sleep quality, and hot flashes.

RESULT(S)

Compared to placebo, escitalopram significantly reduced hot flash interference by 6.0 points at week 4 and 3.4 points at week 8 more than placebo. Reductions in hot flash interference correlated with changes in hot flash diary variables. However, baseline variables did not significantly predict reductions in hot flash interference.

CONCLUSION(S)

Escitalopram (10-20 mg/d) for 8 weeks improves women's quality of life and this benefit did not vary by demographic, clinical, mood, sleep, or hot flash variables.

CLINICAL TRIAL REGISTRATION NUMBER

NCT00894543.

The effect of red clover isoflavone supplementation over vasomotor and menopausal symptoms in postmenopausal women

OBJECTIVE

To evaluate the effect of red clover isoflavone supplementation over vasomotor and overall menopausal symptoms in postmenopausal women.

METHODS

One hundred and nine postmenopausal women aged 40 or more were assigned to randomly receive either two daily capsules of the active compound (80 mg red clover isoflavones, Group A) or placebo of equal appearance (Group B) for a 90-day period. After a washout period of 7 days, medication was crossed over and taken for 90 days more. Daily hot flush and night sweat frequency and overall menopausal symptom intensity (Kupperman Index) were measured at baseline, 90, 97 and 187 days.

RESULTS

Daily hot flush/night sweat frequency and Kupperman Index values were similar in both studied groups at baseline. All indices significantly decreased after red clover phase in Group A, corresponding, respectively to a 73.5%, 72.2% and 75.4% average decrement. These decrements were significantly higher than those observed for Group B after placebo phase (8.2%, 0.9% and 6.7% respectively). In Group A, after washout and placebo phases all values significantly increased. In Group B, all indices remained similar after placebo and washout phases, however significantly dropping after red clover treatment. These values were also significantly lower than those observed in Group A after placebo phase. No side effects were encountered after treatment with the active compound or placebo.

CONCLUSION

Red clover isoflavone supplementation was more effective than placebo in reducing daily vasomotor frequency and overall menopausal intensity in postmenopausal women.

Short and long term effects of tibolone in postmenopausal women

BACKGROUND

Tibolone is an option available for the treatment of menopausal symptoms, based on short-term data on its efficacy. However, there is a need to consider the balance between the benefits and risks of tibolone as there are concerns about breast and endometrial cancer as well as stroke.

OBJECTIVES

To evaluate the effectiveness and safety of tibolone in treating postmenopausal women.

SEARCH METHODS

We searched the Cochrane Menstrual Disorders and Subfertility Group (MDSG) Specialised Register (19 April 2011), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, 2nd Quarter), MEDLINE (from inception to 19 April 2011), EMBASE (1980 to week 3 April 2011), PsycINFO (1806 to week 3 April 2011), Clinical Trials.gov (30 April 2011). Individual researchers and the current manufacturer of tibolone were contacted to identify unpublished and ongoing trials.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that compared tibolone versus placebo, estrogens or combined hormone replacement therapy (HT) by assessing the percentage of women with menopausal symptoms, the severity of those symptoms and the occurrence of safety outcomes in postmenopausal women.

DATA COLLECTION AND ANALYSIS

Four review authors independently extracted information from the articles, resolving discrepancies by consensus. All outcomes studied were dichotomous. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using the random-effects model. Heterogeneity of studies was taken into account before deciding to combine the data.

MAIN RESULTS

When compared to placebo, tibolone was more effective in relieving the frequency of vasomotor symptoms (two RCTs, n = 847; OR 0.42, 95% CI 0.25 to 0.69), although only the 2.5 mg/day dose of tibolone was significantly better than placebo; but with increased vaginal bleeding (seven RCTs, n = 7462; OR 2.75, 95% CI 1.99 to 3.80). When compared to equipotent doses of combined HT, tibolone reduced vaginal bleeding (15 RCTs, n = 6342; OR 0.32, 95% CI 0.24 to 0.42) but was less effective in relieving the frequency of vasomotor symptoms (two RCTs, n = 545; OR 4.16, 95% CI 1.50 to 11.58).As for long term safety, two major RCTs of tibolone versus placebo provided the most relevant data. An RCT of 3098 women with breast cancer and menopausal symptoms was halted after 3.1 years because of increased tumour recurrence (OR 1.50; 95% CI 1.21 to 1.85). However, in another RCT that selected osteoporotic women with negative mammograms (n = 4506) tibolone was associated with a reduction in breast cancer compared to placebo after 2.8 years (OR 0.32, 95% CI 0.13 to 0.79) although the trial was not specifically designed to assess that outcome and the number of overall events was low. In the same RCT, an excess risk of stroke was observed (OR 2.18, 95% CI 1.12 to 4.21). There was no clear evidence of a tibolone effect on endometrial cancer compared with placebo given the low number of events (seven RCTs, n = 8152; OR 1.98, 95% CI 0.73 to 5.32).There was no evidence of a difference in long term safety between tibolone and combined HT.

AUTHORS' CONCLUSIONS

Tibolone, used at the daily dose of 2.5 mg, may be less effective than combined HT in alleviating menopausal symptoms although it reduced the incidence of vaginal bleeding. There was evidence that treatment with combined HT was more effective in managing menopausal symptoms than was tibolone. Available data on the long term safety of tibolone is concerning given the increase in the risk of breast cancer in women who had already suffered from breast cancer in the past and in a separate trial the increase in the risk of stroke in women whose mean age was over 60 years. Similar concerns may exist for estroprogestins but their overall benefit-risk profile is better known and is more directly related to women with menopausal symptoms.

Treatment of hyperhidrosis with botulinum toxin

Botulinum toxin type A is a safe and effective method for treating focal hyperhidrosis, providing longer-lasting results than topical treatments without the necessity of invasive surgical procedures. Although more useful for axillary hyperhidrosis, botulinum toxin injections can also be effective in treating palmar and plantar disease. The effects of botulinum toxin last for six to nine months on average, and treatment is associated with a high satisfaction rate among patients. In this article, the authors discuss their preferred methods for treating axillary, palmar, and plantar hyperhidrosis. This article serves as guide for pretreatment evaluation, injection techniques, and posttreatment care.

Black cohosh (Cimicifuga racemosa) in tamoxifen-treated breast cancer patients with climacteric complaints - a prospective observational study

OBJECTIVE

The antihormonal therapy of breast cancer patients with the antiestrogen tamoxifen often induces or aggravates menopausal complaints. As estrogen substitution is contraindicated, herbal alternatives, e.g. extracts of black cohosh are often used.

DESIGN

A prospective observational study was carried out in 50 breast cancer patients with tamoxifen treatment. All patients had had surgery, most of them had undergone radiation therapy (87%) and approximately 50% had received chemotherapy. Every patient was treated with an isopropanolic extract of black cohosh (1-4 tablets, 2.5 mg) for 6 months. Patients recorded their complaints before therapy and after 1, 3, and 6 months of therapy using the menopause rating scale (MRS II).

RESULTS

The reduction of the total MRS II score under black cohosh treatment from 17.6 to 13.6 was statistically significant. Hot flashes, sweating, sleep problems, and anxiety improved, whereas urogenital and musculoskeletal complaints did not change. In all, 22 patients reported adverse events, none of which were linked with the study medication; 90% reported the tolerability of the black cohosh extract as very good or good.

CONCLUSIONS

Black cohosh extract seems to be a reasonable treatment approach in tamoxifen treated breast cancer patients with predominantly psychovegetative symptoms.

Greater exercise sweating in obese women with polycystic ovary syndrome compared with obese controls

PURPOSE

We examined estradiol and testosterone effects on thermoregulation in women with and without Polycystic Ovary syndrome (PCOS). We hypothesized that core temperature (Tc) threshold for sweating during exercise is delayed in women with PCOS and that testosterone delays the Tc set point for sweating during exercise.

METHODS

For 16 d, we suppressed estrogens, progesterone, and testosterone with a gonadotropin-releasing hormone antagonist (GnRHant) in seven women with and seven women without PCOS (control); we added 17[beta]-estradiol (0.2 mg.d-1, two patches) on days 4-16 (E2) and testosterone (2.5 mg.d-1, orally) on days 13-16 (E2 + T). Under each hormone condition, subjects cycled in a temperature of 35 degrees C at 60% of age-predicted HRmax for 40 min.

RESULTS

Tc sweating threshold was lower in women in the PCOS group compared with those in the control during GnRHant (37.21 degrees C +/- 0.51 degrees C vs 37.70 degrees C +/- 0.12 degrees C, P < 0.05); neither E2 nor E2 + T influenced the thermoregulatory responses in PCOS. E2 decreased Tc sweating threshold in control (37.06 degrees C +/- 0.69 degrees C, P < 0.05), but E2 + T attenuated this response (37.53 degrees C +/- 0.19 degrees C). Peak sweating rate was greater in women in the PCOS group compared with those in the control group during GnRHant (1.06 +/- 0.47 vs 0.47 +/- 0.11 mg.cm-2.min-1) and E2 + T (0.85 +/- 0.41 vs 0.44 +/- 0.10 mg.cm-2.min-1, P < 0.05). Compared with the control group, total sweat losses were greater in the PCOS group during GnRHant (0.614 +/- 0.189 vs 0.419 +/- 0.098 L) and during E2 + T (0.696 +/- 0.281 vs 0.434 +/- 0.164 L, P < 0.05) but not during E2 (0.639 +/- 0.231 and 0.505 +/- 0.214 L for PCOS and control groups, respectively, P = 0.09).

CONCLUSIONS

Thermoregulation was adequate in women with PCOS; however, the women with PCOS achieved thermoregulation at the expense of producing higher sweat volumes.

Treatment of generalized hyperhidrosis with oxybutynin in post-menopausal patients

Postmenopausal hyperhidrosis is a form of secondary hyperhidrosis, and hormone-replacement therapy is a commonly used therapeutic option. However, some women do not benefit from this treatment, and oral anticholinergics are a logical alternative for reducing generalized sweating in these patients. Twenty-one patients were medicated with 5 or 10 mg of oxybutynin per day. After a 3-month follow-up period, efficacy was assessed with the Hyperhidrosis Disease Severity Scale (HDSS) and the Dermatology Life Quality Index (DLQI) was used to assess the improvement in patients' quality of life. The HDSS score was 3.2 +/- 0.4 (mean +/- SD) before medication and 1.9 +/- 0.4 after 3 months. The baseline DLQI score of 8.4 +/- 1.0 was reduced to 4.4 +/- 0.9. No serious side-effects or adverse events resulted from treatment. Oxybutynin was a well-tolerated, effective, and safe method for treating postmenopausal sweating. However, long-term medication and the limited effects of the treatment were disadvantages.

Eccrine sweat response in children with asthma

BACKGROUND

Even though there is a general conviction among parents of asthmatic children and pediatricians that asthmatic children sweat more than healthy ones, this has not been formally tested.

AIM

To determine sweating response and factors affecting this response in children with asthma and compare these findings with healthy children.

METHOD

Eighty-two children with asthma and 51 healthy controls aged 6-18 years were enrolled in the study. Transepidermal water loss (TEWL) was measured on palmar, volar, forehead, and back surfaces before and after exercise and was expressed as the difference between the measurements recorded before and after exercise.

RESULTS

Transepidermal water loss measurements (after exercise - resting) on the palmar surface were higher in children with asthma [22.8 g/m(2 )h (15-34.3)] compared with healthy children [15.2 g/m(2) h (6-22.2)] (P < 0.001). However, a gender stratified analysis showed that the TEWL measurements were higher on all surfaces only in boys but not in girls. Within the group of asthmatic children, TEWL measurements on the volar surface and back were lower in patients using anti-inflammatory therapy compared with those who were on as needed bronchodilator therapy only.

CONCLUSION

Our results show that asthma is associated with a higher rate of sweating response to exercise in boys, and anti-inflammatory treatment decreases the amount of sweating. The relationship of eccrine sweating with muscarinic receptor response and methacholine hyperresponsiveness remains to be determined.

A novel highly effective therapy for severe vasomotor symptoms in an estrogen deficient woman--case report

PURPOSE

To describe a novel highly effective therapy for vasomotor symptoms associated with diminished oocyte reserve.

METHODS

A 58-year-old estrogen deficient woman with severe vasomotor symptoms was treated with 20 mg per day of dextroamphetamine sulfate.

RESULTS

A marked immediate improvement was noted.

CONCLUSIONS

An acquired disorder of the sympathetic nervous system may be the etiologic factor for vasomotor symptoms in women with diminished egg reserve and treatment with sympathomimetic amines seems highly effective. This case will hopefully stimulate a larger series to determine its efficacy in a larger population.

Is active sweating during heat acclimation required for improvements in peripheral sweat gland function?

We investigated whether the eccrine sweat glands must actively produce sweat during heat acclimation if they are to adapt and increase their capacity to sweat. Eight volunteers received intradermal injections of BOTOX, to prevent neural stimulation and sweat production of the sweat glands during heat acclimation, and saline injections as a control in the contralateral forearm. Subjects performed 90 min of moderate-intensity exercise in the heat (35 degrees C, 40% relative humidity) on 10 consecutive days. Heat acclimation decreased end-exercise heart rate (156 +/- 22 vs. 138 +/- 17 beats/min; P = 0.0001) and rectal temperature (38.2 +/- 0.3 vs. 37.9 +/- 0.3 degrees C; P = 0.0003) and increased whole body sweat rate (0.70 +/- 0.29 vs. 1.06 +/- 0.50 l/h; P = 0.030). During heat acclimation, there was no measurable sweating in the BOTOX-treated forearm, but the control forearm sweat rate during exercise increased 40% over the 10 days (P = 0.040). Peripheral sweat gland function was assessed using pilocarpine iontophoresis before and after heat acclimation. Before heat acclimation, the pilocarpine-induced sweat rate of the control and BOTOX-injected forearms did not differ (0.65 +/- 0.20 vs. 0.66 +/- 0.22 mg x cm(-2) x min(-1)). However, following heat acclimation, the pilocarpine-induced sweat rate in the control arm increased 18% to 0.77 +/- 0.21 mg x cm(-2) x min(-1) (P = 0.021) but decreased 52% to 0.32 +/- 0.18 mg x cm(-2) x min(-1) (P < 0.001) in the BOTOX-treated arm. Using complete chemodenervation of the sweat glands, coupled with direct cholinergic stimulation via pilocarpine iontophoresis, we demonstrated that sweat glands must be active during heat acclimation if they are to adapt and increase their capacity to sweat.

Well-being at onset of hormone replacement therapy: comparison between two continuous combined regimens

OBJECTIVES

To compare the effect on well-being of two continuous combined hormone replacement therapies (HRTs) in women starting treatment ('starters') and women switching from mainly sequential HRT ('switchers').

METHODS

This was a randomized, double-blind, 1-month trial, in which 249 postmenopausal women were treated with either conjugated estrogen plus medroxyprogesterone acetate (CE/MPA 0.625 mg/5 mg) or 17beta-estradiol plus norethisterone acetate (E2/NETA 2 mg/1 mg) continuously. Twelve items for measuring climacteric symptoms and well-being were reported daily on a validated symptom scale.

RESULTS

Women taking CE/MPA reported lower scores for breast tenderness (p = 0.005), depression (p = 0.019), irritability (p = 0.004) and tension (p = 0.048), compared with women taking E2/NETA. Compared with pretreatment, both groups developed side-effects during the first week: breast tenderness, swelling and depression (p < 0.05). Starters, but also switchers, improved in sweats (p < 0.001 and p = 0.030). Compared with pretreatment ratings, switchers reported higher scores for breast tenderness (p < 0.001), depression (p = 0.050) and negative effects on daily life (p < 0.001), whereas starters reported only physical side-effects (p < 0.05). A history of premenstrual syndrome (PMS) predicted high scores for swelling (p = 0.023), depression (p = 0.024), tension (p = 0.009), irritability (p = 0.027), headache (p < 0.001) and negative effects on daily life (p < 0.001).

CONCLUSIONS

CE/MPA 0.625 mg/5 mg is better tolerated than E2/NETA 2 mg/1 mg, and starters react differently from switchers. Side-effects occur more quickly than benefits with HRT, and are more frequent in women with previous PMS.

Association between diabetic-autonomic-C-fibre-neuropathy and medial wall calcification and the significance in the outcome of trophic foot lesions

The role of peripheral autonomic nerve failure in the development of medial arterial calcification is discussed controversially in the literature. In addition, the influence of medial wall calcification in the development of trophic foot lesions is still not fully understood. We have compared 28 diabetic patients with cardiac autonomic failure and/or decreased acetylcholine-induced sweat response with 22 diabetic patients without evidence of diabetic neuropathy and 27 healthy control subjects. A strong association was found between medial wall calcification and diminished heart rate variation (p.001) or diminished peripheral sweat response (p < 0.001). Only one subject in the control group exhibited a calcification of the tunica media in the lower limb. Medial calcinosis was accompanied by a significant rise of systolic ankle blood pressure (p < 0.05). In addition, there was a strong relationship between medial wall calcification and trophic foot lesions (p < 0.0001). Our results demonstrate a strong association between sympathetic C-fibre neuropathy and the development of medial wall calcification, as well as between calcification of the tunica media and trophic foot ulceration. Further investigation is necessary to determine whether there is a causal connection between medial arterial sclerosis and diabetic foot ulceration, or whether both are independent consequences of diabetic neuropathy.

An open-label trial of the efficacy of 15% aluminum chloride in 2% salicylic acid gel base in the treatment of moderate-to-severe primary axillary hyperhidrosis

Primary focal hyperhidrosis (HH) is a chronic disorder of excessive sweating. A single-center, open-label study was performed to determine the efficacy and safety of 15% aluminum chloride (AC) in 2% salicylic acid gel base (SAGB) Hydrosal in adults with moderate-to-severe primary axillary HH. Thirty subjects were given 15% AC in 2% SAGB to apply to their bilateral axillae nightly for the first week, then twice-weekly application as tolerated. The primary objective was change in mean Hyperhidrosis Disease Severity Score (HDSS) score from baseline to week 4. Participants who achieved an HDSS score < 2 were designated as "responders." Mean change in HDSS from baseline to week 4 was 1.32 (p = 0.0001). At week 4, 21 of 29 (72%) were responders, and at week 12, 18 of 25 (72%) were responders. Based on these results, 15% AC in 2% SAGB may be an effective, high-strength AC topical therapy for treatment of patients with moderate-to-severe axillary HH.

MF-101, an estrogen receptor beta agonist for the treatment of vasomotor symptoms in peri- and postmenopausal women

During peri- and postmenopausal stages, the majority of women experience moderate-to-severe vasomotor symptoms, such as hot flashes and night sweats, that interfere with sleep and reduce quality of life. Estrogen alone or in combination with a progestagen has been the standard therapy for such vasomotor symptoms; however, this therapeutic regimen is associated with severe side effects, such as breast cancer or cardiovascular events. To provide a better treatment option for menopausal women, Bionovo Inc is developing the estrogen receptor (ER)beta-selective agonist MF-101. Selective ER agonists can stimulate either ERalpha or ERbeta and induce tissue-specific estrogen-like effects, thus providing a safer alternative to conventional hormone therapy. MF-101 is derived from 22 herbs that are traditionally used in Chinese medicine for the treatment of menopausal symptoms. MF-101 did not promote the growth of breast cancer cells or stimulate uterine growth in preclinical studies and, in a phase II trial, was demonstrated to be safe and more effective in reducing the frequency and severity of hot flashes in postmenopausal women compared with placebo. To confirm the safety and efficacy of MF-101, larger phase III trials were planned for 2009. Although MF-101 appears to be a promising therapeutic, the herbal composition of the drug may be a disadvantage, because of the increased risk of causing allergic reactions in the general population. Studies with the MF-101-isolated active compounds liquiritigen and chalcone demonstrated selectivity for ERbeta, with no induction of proliferative events. If these isolates were demonstrated to be as effective and safe in clinical trials as preliminary data suggest regarding MF-101, these compounds could change the way clinicians treat menopause-associated symptoms.

Tropical Malaysians and temperate Koreans exhibit significant differences in sweating sensitivity in response to iontophoretically administered acetylcholine

Natives of the tropics are able to tolerate high ambient temperatures. This results from their long-term residence in hot and often humid tropical climates. This study was designed to compare the peripheral mechanisms of thermal sweating in tropical natives with that of their temperate counterparts. Fifty-five healthy male subjects including 20 native Koreans who live in the temperate Korean climate (Temperate-N) and 35 native tropical Malaysian men that have lived all of their lives in Malaysia (Tropical-N) were enrolled in this study after providing written informed consent to participate. Quantitative sudomotor axon reflex testing after iontophoresis (2 mA for 5 min) with 10% acetylcholine (ACh) was used to determine directly activated (DIR) and axon reflex-mediated (AXR) sweating during ACh iontophoresis. The sweat rate, activated sweat gland density, sweat gland output per single gland activated, and oral and skin temperature changes were measured. The sweat onset time of AXR (nicotinic-receptor-mediated) was 56 s shorter in the Temperate-N than in the Tropical-N subjects (P < 0.0001). The nicotinic-receptor-mediated sweating activity AXR (1), and the muscarinic-receptor-mediated sweating activity DIR, in terms of sweat volume, were 103% and 59% higher in the Temperate-N compared to the Tropical-N subjects (P < 0.0001). The Temperate-N group also had a 17.8% (P < 0.0001) higher active sweat gland density, 35.4% higher sweat output per gland, 0.24 degrees C higher resting oral temperature, and 0.62 degrees C higher resting forearm skin temperature compared to the Tropical-N subjects (P < 0.01). ACh iontophoresis did not influence oral temperature, but increased skin temperature near where the ACh was administered, in both groups. These results suggest that suppressed thermal sweating in the Tropical-N subjects was, at least in part, due to suppressed sweat gland sensitivity to ACh through both recruitment of active sweat glands and the sweat gland output per each gland. This physiological trait guarantees a more economical use of body fluids, thus ensuring more efficient protection against heat stress.

[Clinical study of patients with benzodiazepine dependence, hospitalised between 2006-2008]

The authors present the result of retroprospective clinical diagnosis on benzodiazepines dependence hospitalised in the Drug-Dependence Clinic from the Clinical Hospital of Psychiatry "Socola" Iaşi between January 2006-September 2008.

MATERIAL AND METHOD

The study included a number of 49 patients.

RESULTS

The present article consists of data covering current issues in the area of benzodiazepine side effects. The most frequent clinical manifestations were depression (62.5%), anxiety (52%), perspiration (43%), insomnia (31%), cognitive symptoms (25.2%).

Significant correction of disease after postnatal administration of recombinant ectodysplasin A in canine X-linked ectodermal dysplasia

Patients with defective ectodysplasin A (EDA) are affected by X-linked hypohidrotic ectodermal dysplasia (XLHED), a condition characterized by sparse hair, inability to sweat, decreased lacrimation, frequent pulmonary infections, and missing and malformed teeth. The canine model of XLHED was used to study the developmental impact of EDA on secondary dentition, since dogs have an entirely brachyodont, diphyodont dentition similar to that in humans, as opposed to mice, which have only permanent teeth (monophyodont dentition), some of which are very different (aradicular hypsodont) than brachyodont human teeth. Also, clinical signs in humans and dogs with XLHED are virtually identical, whereas several are missing in the murine equivalent. In our model, the genetically missing EDA was compensated for by postnatal intravenous administration of soluble recombinant EDA. Untreated XLHED dogs have an incomplete set of conically shaped teeth similar to those seen in human patients with XLHED. After treatment with EDA, significant normalization of adult teeth was achieved in four of five XLHED dogs. Moreover, treatment restored normal lacrimation and resistance to eye and airway infections and improved sweating ability. These results not only provide proof of concept for a potential treatment of this orphan disease but also demonstrate an essential role of EDA in the development of secondary dentition.